METHODS & MATERIALS

Home Composting Notes

                                                                                                                       

Home composting

            Which will it be, the garbage, or the garden?

            In nature, organic material is either recycled or sequestered.

The US Waste Stream: Over 60% of our solid waste is organic material.

            Metals                                      8.6%                             
            Glass                                        4.8%

            Rubber, leather, & textiles       8.3%                
            Plastics                                    12.3%

            Paper                                        28.2%                   
           Wood                                        6.5%

            Yard trimmings                       13.7%             
            Food scraps                             14.1%

                                                                                                      - Data from Cornell University, 2009

§         More than ¼ of our solid waste is yard and food waste

§         Food waste is now about 1400 calories/day/person; this amount has doubled in <40 years.

§         Energy use in US food production and distribution exceeds 50 kWh per person per day.

§         Less than 2.5% of US food waste is composted; the other 30 million tons/year goes to landfills or is incinerated.

§         An estimated 72% of US landfills leak pollutants into groundwater.

§         Landfill gas recovery (methane) averages 20% efficiency; 50% is a reasonable target.  Methane is many times worse than CO2 as a "greenhouse gas."

Dollars & Sense

Home composting has many economic and environmental advantages.  It’s a convenient, practical way of disposing of many organic waste materials, e.g., kitchen, yard, and garden waste.

Economics

·         Reduces disposal costs

      -  Ever-growing landfills, incinerator systems: ~$50/ton initial cost

      -  Waste transportation

      -  Water purification

·         Improves value of the land

            -  Sequesters soil toxins, e.g., heavy metals, & reduces erosion from runoff

            -  Improves structure and fertility of soils over long periods

            -  Reduces loss of useful land to trash-related activities

·         Reduces food costs, and ultimately health care costs

            -  Cheap, long-lasting fertilizer with complete range of nutrients and many benefits

            -  Reduces petroleum consumption for fertilizer production, food and waste transportation

      -  Improves soil structure, minimizing the impact of drought

            -  Releases heat that can kill pathogens, pests, and some weed seeds

            -  Decreases plant vulnerability to many pathogens

            -  Buffers against plant vulnerability to non-optimum soil pH (acidity or alkalinity)

            -  Facilitates nutrient cycling in soils; healthier soil à healthier plants à healthier people

Environment

·         Sequesters carbon, reducing our contribution to ever-increasing atmospheric CO₂ levels

·         Reduces landfill leakage of methane into the air and toxic chemicals into groundwater

·         Reduces emissions from trash hauling, incinerators, open dumps and burning

Costs of NOT Composting

• Disposal: transportation, landfill operation, water purification
• Lawns & gardens
• $5 billion/year for lawn fertilizers, 40,000 tons of lawn pesticides
• Less than half of the nutrients in chemical fertilizers is used by plants
• Compost can greatly reduce plant dependence on other soil additives
• Indirect costs: long-term nutrient losses, water quality issues, food & health care costs

 Carbon Emissions

• Since 1850, almost 30% as much carbon has been lost to the atmosphere from the soil organic pool as from all types of fossil fuel combustion.

• Just 5/16” of compost on the average suburban lawn = CO₂ emission from the average car for a year

What to Compost: some brown, some green: ratio about 2 to 1

• Good carbon to nitrogen (C:N) ratio: 30:1
• Good “finished” compost C:N ratio ~15:1

  à About half of the carbon in composted materials is retained; this can be directly added to the soil organic pool.

Carbon lost to the atmosphere since 1850:        Global potential for soil carbon sequestration:

   ~270 billion tons from fossil fuel combustion     ~1 billion tons/year with better land use

   ~78 billion tons from the soil organic pool          That would also improve global food security.

Some notes on the environment

            The atmospheric CO₂ content is about 31% higher than in 1750.  Land use change has caused about ¼ of that increase, around 80 Gt (80 billion tons) of carbon since 1850; combustion of fossil fuels is responsible for most of the remainder (around 270 Gt since 1850).  For comparison, total amounts of carbon present are about as follows:

            Oceans                         38,000 Gt                      Geologic deposits          3,700 Gt

            Soil                               2,300 Gt                        Atmosphere                  760 Gt

            Agricultural soils have lost about ~½ of their “original” organic content, about 15 tons/acre or 11 oz/sq ft of carbon in 150 years.  It has been estimated that environmentally responsible large scale land management practices such as conservation tillage (no-till), mulch farming, cover crops, integrated nutrient management, use of manure & compost, & agroforestry can reasonably replace up to ~0.4 tons/acre, leading to roughly a 40-year replacement time.  In the US, significant recovery of sequestered carbon both in-ground (soil) and above-ground (living plants) has occurred since the peak of agricultural clearing in the 1930’s, mainly because of fire suppression and woody encroachment and reforestation of abandoned farms.  Distribution of carbon sequestered in the US has shifted somewhat to the South; our northern forests have been slower to recover.

            The total land area of the 48 conterminous states is about 2,960,000 sq mi.  Lawns and other mowed turfgrasses (e.g., golf courses) comprise ~63,000 sq mi, or 2.14% or 27.6 million acres (average home: 1/5 acre of lawn).  In spite of many efforts to the contrary, grass clippings are still removed and discarded from much of this area and their nutrients replaced by adding petroleum-based fertilizers.  One acre of turfgrass can typically sequester ~800 lb of carbon in a year.  This is a little less than 10% of the amount that would be sequestered by adding an inch of compost to a growing savannah-type area each year, but it is nevertheless significant because it can replace a net loss of carbon with a net gain.

            The US produces over 1600 lb of trash per person each year; we use about 680 lb of paper per person.  Most of that is compostable, yet much of it ends up in landfills at an average cost of about $50/ton.  About half of our household waste is organic, and about a quarter of it (roughly a pound per day) is kitchen waste.  The total carbon sent to landfills per year per household is over 10% of that emitted each year by the average car.

What to Compost—More Detail
    

Materials high in carbon	Avg C:N	Materials high in nitrogen	Avg C:N
Autumn leaves (better shredded)	30-80:1	Vegetable scraps	12-20:1
Straw	48-128:1	Coffee grounds	20:1
Wood chips, sawdust, bark	100-750:1	Grass clippings	12-25:1
Newspaper, corrugated cardboard	400-800:1	Fresh garden waste	20:1
		Cow manure	20:1
		Poultry manure	5-15:1

   

Also add some compost or good garden soil to any compost pile to provide a population of “decomposers.”

If you mulch with straw, this year’s mulch becomes future years’ compost.

            Anything that was once alive can be composted.  Yard wastes and some kitchen scraps are good examples.  Woody yard wastes can be shredded for mulching and path-making, where they will eventually decompose and become compost.  Following are some additional suggestions:

            Egg shells (best to rinse first)

            Uncooked fruit wastes, e.g., banana peels high in K

                        Note: fruit wastes may attract pests

            Hay, especially alfalfa

            Peanut shells

            Pine needles (very acid)

            Wood ashes (very alkaline—use small amounts)

Notes:

            Sawdust, wood chips, shavings break down slowly and “borrow” soil nitrogen.

            Straw is excellent for aeration; also use as mulch; year-old straw breaks down faster.

            When using weeds, add to compost before seeds set.

For an extensive list of compostable materials with their nutrient contents, see the book by Kourik in Resources, above, Appendix 5.

Compost—“Recipes”...as many as there are composters

•          Use what you have, but...

–         Most woody plants & some perennials like compost with more fungal content (àNH₄+)

–         Most vegetables, other annuals, & grasses prefer compost with more bacterial content (àNO₃-)

•         Plants tend to prefer compost made from higher percentages of the same or similar plants—just what they get in natural environments!

Harvard University Compost Recipes

      Start with three sets of ingredients:

            A - Bacterial feedstocks: hay, weeds, other herbaceous plant materials, coffee grounds

            B - Fungal feedstocks: dry leaves, sawdust, wood chips, shredded newspapers

            C - High-nitrogen materials: grass clippings, vegetable waste, legumes, animal manure

      Two final mixes:

            Bacterial mix         45% A, 30% B, 25% C

            Fungal mix            30% A, 45% B, 25% C

What NOT to compost

    Generally Avoid:

•          Meat, dairy products, oils (invite pests)

•           Dog or cat feces (may contain potentially harmful parasites)

•           Diseased plants (unless certain of hot compost)

•           Invasive weed fragments and seeds (ditto)

•           Manure from animals fed large amounts of antibiotics

•          Composting reduces antibiotic levels by up to 99%

    Avoid—use alternate disposal methods

•          Glossy paper, especially if colored (possible toxicity)

•          Any materials treated with persistent herbicides, pesticides

            Data are sparse and inconsistent on effects of heat over time on germination of weed seeds.  If unsure, test, make a solar “cooker,” or as a last resort, add to material destined for landfills.

Composting Methods

ü       Hot versus cold...and various levels of “lukewarm”

ü       The Felder Rushing method

ü       Mimicking Nature’s methods

                  - Above surface

                  - Below surface

ü       Bins & containers

ü       Worms at work

ü       The best I know of: using straw bales to make a “bin,” and “used” straw in the mix

Cold	Hot
Allows gradual addition of material;   “forgiving”	Much faster compost production
Less maintenance	Uses space efficiently
Preserves more beneficial organisms	Most plant parasites & pathogens die after 3 days   at 130+ degrees
Can conserve more nitrogen	More uniform compost
Many alternatives suitable for backyard   situations	Suitable for larger quantities
Most home composting methods do not result in truly hot composting.

There are about as many approaches to composting as there are people who compost, and almost none of these are “wrong.”  The composting process is forgiving; in time, all organic materials will be reduced to compost.  Following are examples of some approaches.  In most cases, it is best maintain a volume ratio of at least 2:1 or 3:1, “brown” to “green” (high-carbon to high-nitrogen).  This should correspond to a C:N ratio of on the order of 30:1 by weight.  Keep “green” layers thin enough or well enough mixed in with the brown to avoid excessive matting down—compost needs to breathe!   Moisture levels should be kept between roughly 40% and 60% by weight—about as moist as a well wrung out sponge.  By the time the composting process has slowed to a nearly stable state, the volume of a typical pile has been reduced by 55-60%.

Troubleshooting (can apply to hot or cold composting)

•          Prepare for aerobic composting

–         Use <25% manures, other high-nitrogen materials

–         Use <20% leaves, or shred & mix in thoroughly

–         Provide ventilation

•          If noxious odors arise

–         Mix in high-carbon materials, e.g., straw, sawdust

–         Aerate!  There are several types of compost aerating tools (or use a digging fork--whatever works!)

A couple health precautions:

        -  Thermophilic (hot) compost piles may contain large populations of Aspergillus spp. (fungus).

            - Individuals with weakened immune status may be susceptible to Aspergillus infection.

            - Individuals subject to asthma and other respiratory problems should exercise caution, such as using masks, particularly in turning compost piles.

        -  Piles that do not reach a thermophilic stage may harbor pathogens such as those that might be contained in post-consumer food scraps.

                                          See: http://cwmi.css.cornell.edu/health.pdf

“Cold” (or at least not very hot)  Composting

•          Cover crops (many benefits)

•          Mulching and sheet composting (See Weedless Gardening by Lee Reich)

•          Pit or trench composting

•          Commercial composters

•          Home-modified and home-built units

•          Vermiculture

One glance at an area showing a bit of lawn and a bit of vegetable garden may not reveal composting methods.  But there are at least four here:

            Grass clippings dropped by a mulching mower are decomposing amid the lawn grass, providing an effect similar to that of a “cover crop.”

            A trench has been dug at least 12 inches deep, about 5 inches of good compostable material added in the bottom, and the soil replaced over the top.  A row crop will be planted over the trench the following year.

            Small pits about 16 inches deep have been dug, half filled with compostable material including some that might attract pest animals, the soil spread back over the pits, and flat stones placed over them to prevent animals from digging there.

            A sheet of clean finely chopped and mixed compostable material including some straw has been spread between crop rows.  This will act as a mulch, breaking down slowly, providing a steady stream of nutrients to the vegetable roots below while suppressing weed growth.

Notes:

            - A variation of pit composting is the use of a commercially available “digester,” which is the only method recommended for disposal of for pet wastes, meats, fats, etc.

            - Digging a “sheet” of material into the top few inches of the soil will speed the composting process, but care should be taken to avoid compacting the soil.  (Use of a rototiller is not recommended!)  Avoid large pieces of material, especially if woody.  By the following spring, breakdown will be incomplete but may have reached a stage suitable for planting over.

Some references relevant to composting “in place” and the importance of compost in the garden:

            - An “ultimate extension” of sheet composting is described in a popular book, Lasagna Gardening, by Patricia Lanza, 1998.  It’s entertaining, unique, and a good approach to some problem soil situations. Caution: some of the recommendations could lead to problems if not exercised with care, e.g., use of (lots of) grass clippings) and wood ashes.  Also, the use of sphagnum peat is questionable because of sustainability issues.  And unfortunately, the book recommends some invasive alien plants for butterfly and bird gardens.  Lanza's book is the only one I know of that deals specifically with her concept of "extreme layering" for gardens.  Her recipe for building new garden soil by on-site composting looks a bit like the recipe for a compost pile on p.18 of Eliot Coleman's Four Season Harvest (1999 Revision), which I strongly recommend.

            - Weedless Gardening, by Lee Reich, 2001, provides a simple, easy-to-read, logical approach to growing almost anything.  This is the book I buy for friends most often, as I believe it to be the best available starting place for a first-time gardener.  It describes the "top down" rationale that's at the heart of the concept.  Reich obviously understands the vital role of microorganisms in soils.

            - A truly timeless classic gardening book is How to Have a Green Thumb Without an Aching Back, Ruth Stout, 1955.  Paraphrasing Robert Kourik, Stout stoutly tilled her garden for 14 years until she realized she didn't have to.

            -  Roots Demystified, Robert Kourik, 2008,  is the best easy-to read discussion I’ve seen on how plants get nourishment from their growing medium.  Kourik's (much) earlier book, Designing and Maintaining Your Edible Landscape Naturally, 1986, was my most frequently opened book until I bought the one by Lowenfels & Lewis (below).  Kourik is a thorough, thoughtful author.

            - B: Teaming with Microbes, Jeff Lowenfels & Wayne Lewis, 2010, is by far the best readable explanation to date of the living soil.  This may be the most important widely distributed gardening book of this century so far.  It’s not too well organized, but definitely worth plowing through.  You'll never use a rototiller again.

            - Roots and Soil Management: Interactions Between Roots and the Soil, Richard W Zobel & Sara F Wright, Editors, 2005, is a tough read.  Sara Wright (my hero!) discovered and named "glomalin" (glow-MAY-lin) in 1996.  Glomalin is a substance (a glycoprotein) secreted by beneficial fungi.  It's very important in giving "good" soil its structure, and in overall soil carbon sequestering. 

Be a “Has Bin”!

Another type of home composting, which I recommend VERY strongly, is vermiculture, or worm composting.  The book Worms Eat My Garbage by Mary Appelhof provides an excellent introduction, best for grades 5 and above.  This is an indoor, year-round activity that’s a natural for involving kids.  I truly believe this quote: “The most important result of home composting may be the impressions we leave with our children.”

Vermiculture notes:

•          Turn kitchen waste into high-quality compost

•          Inexpensive to make from plastic storage bin

•          Purchase Eisenia foetida (red wiggler, branding worm)

–         Not Lumbricus rubellus or  Lumbricus terrestris

–         Both E. foetida and L. rubellus are sometimes called “redworms.”

                       

Worm “castings” are probably the best compost one can “brew” at home.

Contact Trina Ball (balltl@aol.com) for how to enjoy this important home (and school!) composting method! Please note Trina’s article “WORM BIN MAKING 101: A Green Gift That Gives Back!” just below this one.  It gives good instructions on how to make a great bin that costs little…and the worms love it!

My worm bin, courtesy of Trina Ball

Tips:

Worms like about 75% moisture, dark, with well-drained & aerated bedding.

They don’t like vibration.

Worms are in top 6”, 2-3” long.

They should start ~2 months to egg-laying after about 2 months.

Eggs hatch in 3 weeks, 2-7 worms/egg.

Feed kitchen scraps; no salt, cooked foods, acid (citrus), onions, or hard rinds.

Total about 3-3.5 lb/week per lb of worms

Add newspaper if too wet.

Maintain in the range 55-75 degrees, never less than 40 or more than 85.

Fruit fly trap: vinegar and/or pieces of fruit plus a little soap.

Compost Tea

            See the book by Ingham in Resources below.  Addition of compost “tea” is effective in introducing beneficial microorganisms to the soil, speeding toxin breakdown, allowing quick access to nutrients.  Use 2 T worm castings/qt water on plants.

“Lukewarm” Composting

Completely unenclosed piles provide easy access for turning, but need turned a number of times to get uniform composting.  Since they are not insulated, the edges will compost very slowly.  These are best for large-volume operations maintained with power equipment such as a front loader or dedicated compost turning unit.

There are many types of compost “bins” that make composting easier, or at least more manageable, most of which provide for “hot” composting under idea circumstances and with adequate care…or at least a little warmer than the previous methods.  Open bins may be constructed easily from wood, even wood pallets; from various types of fences, concrete blocks, etc.

  Especially in Northern Michigan’s climate with its cool nights, these generally don’t heat up to any significant degree on the outside, and will likely require frequent turning to produce uniform compost.  Open containers are most conveniently used in groups of two or three to facilitate easier turning of composting material from one to another.  These provide little insulation; therefore turning must be carefully done to move outside material to the center of the pile if all material is to reach thermophilic temperatures.

            Many people who do home composting, especially in densely populated areas, find fully contained compost containers desirable for aesthetic purposes.  Some of these can even be used indoors to permit year-round composting.  There are many commercially available containers, or fully enclosed bins, mostly made of plastics.  Most are costly but may be practical over time.  It’s not unusual for individuals to have two such units, one to be “working,” and the other to receive daily additions of new compostable material.  Here’s mine with the product of about 3 months worth of vegetable scraps together with some of the previous year’s straw mulch.  Not a huge batch of compost, but better than adding material to a local landfill!

A cheaper alternative: a garbage can composting unit

Drill numerous holes in a large garbage can and place a perforated PVC pipe vertically into the center of the can.  Add alternating layers of brown (high carbon) and green (high nitrogen) material with 1-2 inch layers of garden soil.  Cover, mix about once a week.  Mixing can be difficult; one recommended method is to use a compost mixing tool or a garden auger driven by a portable electric drill.  Composting usually takes at least 8-10 weeks.

Hot Composting:  “Some (thermophilic bacteria) like it hot.”

    Factors affecting the rate of composting include:

•          Nutrient balance (mainly the C:N ratio)

•          Impurities

•          Moisture (ideal: ~50%)

•          Aeration

•          Surface area of material

•          Size & insulation of pile

Sequence of Events in Hot Composting

            1 - pH initially drops as anaerobic bacteria break down carbohydrates

            2 - pH rises as process becomes aerobic

            3 - Process stabilizes to neutral or slightly basic

Avoid release of volatile organic acids (Phase 1) & excess ammonia (Phase 2) by aerating & adding sufficient high-carbon materials.

The following are tips based in part on the book Four Season Harvest by Eliot Coleman, one of America’s most successful organic gardeners and an excellent garden author.  Coleman recommends an “eclectic” approach: a broad range of plant materials results in a broad range of nutrients in the compost.  Coleman considers straw to be overall the best “brown” material.

Coleman’s “recipe,” which provides fast and efficient compost production, is as follows:

            3” straw

            1-6” loose “green” material

            ¼-1” good garden soil

            Repeat layers....

            The added soil layers introduce microorganisms that begin the composting process, as well as minerals that add to the overall nutrient balance of the product.  In addition to carbon, nitrogen, oxygen, and water, microorganisms require phosphorus, potassium, and trace amounts of calcium, iron, boron, and copper for growth.  Normally the soil addition provides adequate numbers of microorganisms to begin the composting process, but in some cases, local soils may be so poor that addition of a small amount of working compost to a new pile is useful.

            Coleman uses straw bales as the outside structure for his compost operation.  This has many advantages, especially for northern climates.  The straw adds significant insulation that helps piles attain high heat (140 degrees or higher) out to its edges; this may eliminate the need for turning altogether, or at least reduce necessary turning.  Of course, eventually the straw itself breaks down and becomes part of the compost.  Additional insulation may be gained by using loose straw on top of the pile.  Coleman uses a waterproof cover beginning in late fall to help extend the composting action into the cooler period.

            Coleman does not incorporate wood chips into his compost, as they break down slowly and incompletely.  He prefers not to use leaves in his main compost piles because they tend to mat down and prevent aeration.  Also, many leaves contain plant growth inhibitors that are not broken down until they are well composted.  He prefers to maintain separate leaf compost piles in which fungi rather than bacteria perform the digestive process, working more slowly and producing “leaf mold” over a period of 1-2 years.  He uses this product mainly in growing members of the Brassicaceae (e.g., cabbage) and Apiaceae (e.g., carrot) families.

            He uses little or no raw manure (never more than 20%) because it is so nitrogen-rich that it can result in too-rapid oxidation.  If excess ammonia is released in a moist pile, it can react with water to produce ammonium hydroxide, a strong base that can elevate the pH at cell surfaces to as high as 11 or more.  This is toxic to the microorganisms on which the composting process depends.  He feels that horse, cow, and goat manures are best for composting, and that they should be introduced only after substantial preliminary rotting.

            Coleman prefers to use only fine, well-finished compost on his vegetable beds.  This is material that has been turned after it begins to cool, and undergoes another thermophilic (hot) stage.  This is followed by a long mesophilic (cool) period, preferably 1-2 years, after which it is extremely high quality humus.  He applies it on top or in only the top 1-2 inches of his garden soil, letting earthworms and other soil organisms do the work of mixing.

            Piles need some means of allowing air penetration to the centers of piles.  One such method is placing a perforated PVC pipe vertically in the center.  The best method is probably the use of at least some straw, which has the advantages of some stiffness (preventing premature matting down of the pile) together with hollow stems.  Some straw (or some twigs) at the bottom of the pile, where the worst compacting can occur, is especially helpful.  Most piles require turning at least once, and unless they heat up significantly, may take up to 1-2 years to produce “finished” compost.  Minimum size is around 30 cubic feet for attaining high enough temperatures for rapid composting.  Piles greater than about 150 cubic feet can be problematic because not enough oxygen can reach the center of the pile to support aerobic decomposition.

 

Odor Problems

           

            Oxidation processes in composting result in carbon dioxide production.  If the internal CO₂ level approaches 9%, or if the oxygen level drops much below 10%, the process will begin to become anaerobic.  In this case, organic matter is converted to in part to methane, alcohols, volatile fatty acids, ammonia, and hydrogen sulfide (the “rotten eggs” odor); composting becomes slower, and smellier.

Even predominately aerobic composting leads to the loss of at least some nitrogen. This loss is associated with high temperatures, low moisture content and eventual alkaline conditions that are attained during the composting process.  The presence of excess nitrogen in the form of ammonium carbonate or ammonia stems from the microbial metabolism of proteins or other sources of nitrogen.  Microbes use nitrogen in proteins, nucleic &amino acids, enzymes, etc., and for reproduction, growth & function, but carbon comprises up to about ½ of the mass of microbial cells, nitrogen much less.  If the C/N ratio in composting material is too low (less than about 20-25:1), the energy source (carbon, mainly in carbohydrates) may be less than that required for microbial cells to combine with the available nitrogen in their growth. Then the organisms use all of the available carbon and eliminate the excess nitrogen as ammonia.  If excess nitrogen in the decomposing mass is too great, ammonia may be formed in amounts sufficient to be toxic to the microbial population and cause air pollution as well.  It is difficult to amend such high nitrogen sources as poultry manure to avoid release of ammonia.  In large compost operations, it is necessary to scrub exhaust air with water to prevent significant air pollution.  Excessive use of manures (greater than 10-20%) in home compost operations is not recommended.  Further, compost derived from mainly plant materials is typically better balanced in nutrients.  In a properly functioning compost pile, the C:N ratio decreases from around 30:1 initially to about 10-15:1 in the finished product.

Adding finely chopped high-carbon materials such as sawdust can reduce release of free ammonia because not only do such materials provide an extra source of carbon, but they adsorb some of the gaseous ammonia (NH₃).  In general, woody materials are slower to break down than herbaceous plant materials because of the lignin in the cell walls of the wood.  Cellulose, predominant in herbaceous material, consists of chains of glucose molecules, which break down into volatile fatty acids & microbial biomass.  Animal enzymes cannot digest lignin, which is a complex polymer.  Some fungi and bacteria secrete ligninases, which break down part of the lignin; for example, given sufficient nitrogen, only about 20-50% lignin typically breaks down after ~100 days of composting.  For this reason, large amounts of woody materials are not recommended for hot composting operations.

Other Considerations

Small particle size within a compost pile means more total particle surface area; this enables more rapid microbial interactions with the material.  However, sufficient oxygen is also required for microbial growth.  Oxygen comprises about 20% of ambient air; 10% is adequate inside the pile, but if the level drops toward 5%, aerobic bacteria die.  If particle size is too small, or the pile is too compacted, insufficient oxygen may be available, and the process will begin to become anaerobic.  That is, aerobic microorganisms are replaced by anaerobic ones.  This leads to slower breakdown, increased ammonia release, and formation of methane, alcohols, volatile fatty acids, and hydrogen sulfide.  Composting is slower, more nitrogen is lost to the atmosphere, and noxious odors become evident.

The pH (measure of acidity/alkalinity) of a properly working compost pile usually drops initially to around 5.5, then rises to 7-8.5 for the final product.  During aerobic composting, bacteria and fungi release organic acids—this lowers the pH and encourages growth of additional fungi and the breakdown of lignin & cellulose.  The acids then break down further, and the pH rises.  But if the pile becomes anaerobic, the acids can lower pH to as low as 4.5, limiting microbial activity.  Aeration usually restores pH to >5 and allows aerobic bacteria to resume their growth.

A local composting “guru” uses the following very effective approach to support a sizeable home gardening operation:

•          Straw bale “bin” & material

–         Insulation

–         Air circulation

–         No waste

•          Kitchen & garden waste, manure provide nitrogen

•          Small amount of garden soil

•          Build pile all at once on a warm spring day

•          Turn when pile cools

•          Usable compost in 2-3 months

•          Well “finished” by next spring:

Suitable sizes for straw bale compost “bins” are generally in the range from 3 X 3 X 3 to 5 X 5 X 5 feet.  I chose the larger size for mine to assure that it heats up well and can be turned the lazy man’s way: with a 4-foot front loader on my small tractor.

Bin at the Historic Barns Park garden covered and ready to "work"

Sifting Compost

            There are many advantages to using a compost sifter.  Adding finely sifted material before planting creates a fine seed bed, usually improving germination.  Removing larger pieces of partially uncomposted material reduces the “borrowing” of nitrogen that bacteria must use to continue their decomposing function.  When these larger pieces of decomposing material are added to a new compost pile, they add large numbers of microscopic decomposers that accelerate the composting process.

            Sifters are easily made using a simple wood frame and half-inch galvanized hardware cloth.  Here are two designs, one shown in use at a school garden in Leland, and a simple one suitable for sifting into a wheelbarrow or garden cart.  A third design may be seen at the Leelanau Community Garden.

Compost in the garden can:

•          Warm soil in spring (two ways)

•           Prevent weed germination

•           Provide many nutrients to plants

•           Inoculate soil & support beneficial soil life

•           Store & deliver nutrients to plant roots

•           Protect plants from diseases & predators

•           Aerate soil, improve tilth

•           Improve soil structure by forming aggregates

•           Allow oxygen transport & water retention

•           Increase percolation, reduce erosion

•           Enable plants to obtain mineral nutrients (K, Ca, Mg)

•           Buffer soil pH

•           Bind contaminants, help detoxify soil

•           Help sequester carbon in large quantities

Importance of Organic Matter in Soils

            Soils consist in varying amounts of air, water, minerals, and humus.  Humus is the biological constituent of soil, the product of breakdown of organic matter.  A typical “soil triangle” places soils in categories according to the particle sizes of their mineral constituents, in order of decreasing particle sizes: sand, silt, and clay.  For example, the mineral portion of a “medium loam” soil is roughly 40% silt, 40% sand, and 20% clay.  Much of Leelanau County’s soil mineral constituent is predominantly sand, silt, or loamy sand, the latter around 80% sand, 10% silt, and 10% clay.

            The mineral portion of soil is a reserve of many nutrients (see table below), but in their natural forms, these are not typically highly soluble in water; most must be incorporated into humus by microbial organisms before they can be used by plants.  The ability of a soil to take up mineral nutrients is directly related to its “cation exchange capacity,” which is a measure of its number of negatively charged ion exchange sites per unit mass.

            In soils, most anions (negatively charged) are large (macro) ions; therefore, the solid matrix of the soil has a negative charge.  To maintain net electrical neutrality, large numbers of cations (positively charged) are adsorbed onto anion surfaces.  This creates a situation in which some of the adsorbed cations can be readily exchanged for others.

            Humus and clay contain macroions that allow cation exchange.  Humus contains proton-donating groups on the surface of its molecules.  These are undissociated at low pH levels but dissociate as pH rises, resulting in negatively charged surfaces.  The most important of these is the carboxyl group.

            Clay consists of platy aluminosilicate materials; their lattice has a positive charge deficiency caused by substitution of Al+++ for Si4+ or Mg++ for Al+++ in the structure of the crystal, giving the crystal a net negative charge.

            In most agricultural soils, the dominant exchangeable cation is Ca++ with lesser amounts of Mg++, Na+, and K+.  These are the base cations that form the bases Ca(OH)₂, etc.  In acid soils, the acid cation Al+++ is dominant in mineral soils, and H3O+ is dominant in organic soils.

            The cation exchange capacity (CEC) is a measure of the total number of cations that may be exchanged per unit mass of dry soil, e.g., millimoles of negative charge per kilogram of soil on the surfaces of soil particles.

           

            Among sand, loam, silt, clay, and humus, the humus has the highest capacity for ion exchange, and therefore is the material best suited for providing necessary mineral nutrients to plants.  Relatively good soil might, for example, consist (by volume) of 25% air, 25% water, 45% minerals, and 5% organic matter (preferably more—8% is a good goal).  In parts of NW Lower Michigan, the organic component of our soils may be as low as 1-2%; therefore, organic matter must be added before strong, healthy growth of edible and ornamental plants in home gardens can be achieved.  Humus is relatively stable, but continues to decompose slowly over time by oxidation.  Therefore, for strong plant growth to continue, humus must be continually replaced.

Macronutrients - air and water	Carbon (C), Hydrogen (H), Oxygen (O)
Macronutrients - soil	Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), Sulfur (S)
Micronutrients - soil	Iron (Fe), Manganese (Mn), Zinc (Zn), Copper (Cu), Nickel (Ni),Boron (B), Molybdenum (Mo), Chlorine (Cl)
Beneficial nutrients that enhance the growth of some plants.	Cobalt (Co), Silicon (Si), Vanadium (V),  Sodium (Na)

The Decomposers

            Organisms that perform chemical and physical decomposition are at the heart of the two major chemical cycles, those of carbon and nitrogen, that lie at the heart of living organisms’ ability to recycle organic materials in an unbroken chain.  Carbon is necessary for plants to harvest light and use its energy produce simple sugars, their fundamental source of chemical energy, and release oxygen back into the atmosphere.

                               Photosynthesis: 6 CO₂ + 6 H₂O à C₆H₁₂O₆ + 6 O₂

            Plants capture energy from sunlight and use it to perform photosynthesis combining CO₂ and water to form sugars, releasing excess oxygen in the process.  Through respiration, plants use the energy stored in sugars for growth and reproduction.  Nutrients made accessible to plants by The Decomposers facilitate plant growth and the continuation of the carbon cycle.  Nitrogen is often the limiting factor in plant growth.  It is required to produce amino acids, nucleic acids, and chlorophyll.  Plants obtain nitrogen from their environment in two major ways: fixation of atmospheric nitrogen, such as that performed by symbiotic bacteria (Rhizobia) in the root nodules of legumes; and mineralization (ammonification plus nitrification) by The Decomposers.

The Decomposers and Feeders of Plants

The following organization by Cornell University differs from the widely used “trophic level” chart by Elaine Ingham, which begins with plants and “waste” organic matter at the first level.  We use it for simplicity.

For an outstanding review of soil biology and many excellent photos of soil bacteria, fungi, and larger life forms, see http://www.nrcs.usda.gov/wps/portal/nrcs/detailfull/soils/health/biology/?cid=nrcs142p2_053860

Primary level

            Bacteria (including actinomycetes)          Fungi

            Earthworms                                           Snails

            Sowbugs                                               Pot (white) worms

            Flies

                       

Secondary level (feed on primary levels)

            Protozoa                                               Rotifers

            Springtails                                             Mites

            Small beetles                                        Nematodes*

            Millipedes

Tertiary level (feed on primary & secondary levels)

            Ground beetles                                      Pseudoscorpions

            Centipedes                                            Ants--many species

Primary: Bacteria

    Many species, wide temperature range

    Main decomposers in most composting

    Oxidation releases heat (this can be used for extending growing seasons, e.g., in “hotbeds.”)

    Some (rhizobia) “fix” nitrogen from the air

    Many provide plants with nitrogen in nitrate (NO₃-) form

Primary: Actinomycetes (specialized bacteria)

    Decompose cellulose (plants), chitin (fungi, arthropods)

    Recover nutrients

    Help stabilize soil structure

Primary: Fungal hyphae (in rhizosphere)

Decompose “difficult” organic matter (lignin)

Store and transport nutrients

Provide nitrogen in ammonium (NH₄+) form

Critical soil stabilizers

     Note: actinomycetes and fungal hyphae also act as soil structure stabilizers.

à Another Type of Fungi: Glomerales: “Arbuscular Mycorrhizae”

Symbiotic with >90% of plants

Flourish in absence of excess nutrients

Secrete glomalin à Very stable, enhances soil structure and sequesters about 1/3 of soil carbon

Other Primary Decomposers

      Earthworms, white worms, sowbugs, mites….

                  Earthworm “castings” are extremely rich in nutrients.

                  Even flies are important (distribute beneficial bacteria)

Secondary: Protozoa, Rotifers

      Live in water films or droplets

      Feed on bacteria, some fungi, & some partly decomposed organic matter

Secondary: Fungal Feeding Mites, Millipedes, Springtails

      Feed on fungi, “etc.”

      Aerate, recycle nutrients

Secondary/Tertiary: Nematodes

      Some feed on bacteria, fungi, protozoa, protozoa, other nematodes...beneficial

      Some invade plant roots…harmful

Tertiary—Predators: Predatory Mites, Centipedes, Pseudoscorpions

      Feed on many species (including some beneficial worms)

      Aerate, recycle

Final Comments

Much of our original forest duff is long gone from Michigan’s State Soil, Kalkaska Sand.  We have it in our power to replace at least part of that precious resource of organic matter through aggressive efforts to recycle organic material through municipal and home composting.

When we make and use compost in home food production:

• We significantly reduce food costs and fossil fuel energy use for production and transportation.
• We reduce greenhouse gas emission and other air pollution from landfills.
• We reduce water pollution from landfills and runoff from soil.
• We create sources of cleaner, safer, more economical, more nutritious food.
• We lead the way in enabling future generations to make better, energy, food, and environmental choices.

“The most important result of home composting may be the impressions we leave with our children.”

We can live better, and ever more gently upon our planet, if we will but “think like a plant”—that is, if we will, like the plants of the world, synergize, recycle, and sequester.

“Whatever you do may seem insignificant to you, but it is most important that you do it.”

  - Mohandas Gandhi

Some Recommended Reading

•          Books:

–         Four Season Harvest (Eliot Coleman)

–         Worms Eat My Garbage (Mary Appelhof)

–         On-Farm Composting Handbook (See also:

•          http://compost.css.cornell.edu/OnFarmHandbook/onfarm_TOC.html)

–         The Rodale Guide to Composting (1979 and The Rodale Book of Composting, 1992)

–         The Compost Tea Brewing Manual (Dr Elaine Ingham)

–         The One-Straw Revolution, Back to Nature, and The Natural Way Of Farming (Fukuoka Masanobu)

–         Designing and Maintaining Your Edible Landscape Naturally (Robert Kourik)

–         The Real Dirt (Northeast Organic Farming Association) 1998 Revision. See: www.nofany.org/publications.html

–         Teaming with Microbes (Jeff Lowenfels & Wayne Lewis), especially Chapters 16 (Compost),

        17 (Mulch) & 18 (Compost Teas)

–         Weedless Gardening (Lee Reich), especially Chapters 1 (Why Garden from

       the Top Down) and 4 (Portion on Compost)

•          Web Sites:

–         web1.msue.msu.edu/imp/mod02/01500589.html

–         www.css.cornell.edu/compost/Composting_Homepage.html

–         www.wormwoman.com

–         http://ohioline.osu.edu/hyg-fact/1000/1189.html

–         www.mi.nrcs.usda.gov/soils.html

–         http://cwmi.css.cornell.edu/compostbrochure.pdf 1

     

WORM BIN MAKING 101

A Green Gift That Gives Back!

By Trina Ball…the “Worm Lady”

First you'll need a bin similar to this:

Directions below.  There are plenty of commercial alternatives, but this one works well; and it's easy to make, and inexpensive.

Mixing a small amount of partially-decomposed “living” materials into your empty bin is one strategy that helps establish a bin quickly.  Start by scooping up a few hands full of these “living” materials from a variety of sources…a forest, meadow, backyard tree or shrub.  This will transform a sterile environment into one that is well on its way to being a stable habitat for your worms.  Now you can add kitchen veggie scraps and composting worms.  Maintain even “sogginess”, topped with 3-6” shredded dry newspaper.   

The worms and other microbe-loaded biofilters in your mini ecosystem will convert waste, pathogens and gases into something beneficial.  The end product is inexpensive, organic, and locally made.  Next spring your precious “vermicompost” will be ready to condition your soil and feed your garden plants.  Gardening, by the way, accomplishes what grocery stores cannot: getting people to eat more fruits and veggies.  According to Daphne Miller, M.D., a researcher who was raised on a farm and later wrote Farmacology, “56% of gardeners eat the recommended 5+ veggie servings per day while only 25% of non gardeners...”

Your kitchen veggies stripped vital nutrients from somebody’s soil, somewhere.  But those nutrients still exist in your scraps.  The objective here is to cycle these nutrients through your bin ecosystem and back into the production of living matter.  This is the natural process...the back-to-basics Nutrient Cycle that we all learned about in school, if we were paying attention.  Fortunately, there is a growing back-to-basics trend in food production and consumption.  Are you involved?

YOUR HOME-CRAFTED VERMICOMPOSTING  BIN

Lidded 10-gallon container

1" PVC piping cut at about 20" lengths.

Drill bit or hole saw for four 1” PVC insertion holes on sides.

Drill bit for 1/8” aeration holes on lid and in PVC.

YOU WILL ALSO NEED

Biodiversity

      - Compost from backyard compost pile or equivalent...1 scoop.

      - Partially decomposed leafy top soil from a forest, meadow, backyard tree or shrub...1 scoop.

Minerals

      - A pinch of crushed stone and finely ground egg shells (Hint: use your coffee grinder.)  

      - Newspaper or other bedding, shredded by hand or with a paper shredder. Avoid colored ink.

      - Water spritzer/mister.

      - Kitchen scraps. No citrus, meats or dairy, or oils. (Hint: try cooked squash!)

      - Hand rake or equivalent turning/lifting tool

      - Eisenia fetida [or foetida] (red wiggler or branding worm), not Lumbricus rubellus or Lumbricus terrestris. (Both E. fetida and L. rubellus are sometimes called “redworms.”) Order 1 lb. online to start a population.

TIPS FOR GETTING STARTED

      - Use a water mister to maintain spongy, even moisture under a dry top layer of bedding. 

      - When opening the lid, observe worms quickly heading downward, avoiding light, seeking moisture.

      - Worms may initially go into shock and cease eating vigorously until they adapt to their new environment. 

      - Is liquid visible in the bottom of the bin?  Odors?   Gently aerate by turning in dry bedding.         - Leave lid ajar.

      - Overfeeding can result in mold.  Remove mold from bin. 

      - Underfeeding or an otherwise unbalanced environment results in a shrinking population.

      - Occasionally add a top layer of dry shredded paper. (Fruit flies lay eggs on exposed food, moist surfaces).

      - Look for cocoons and worms of all ages. 

      - For more rapid population growth, store at temperatures comfortable for humans.

And be sure to read Worms Eat My Garbage by Mary Appelhof.  It's an excellent guide, especially for getting kids started having fun with raising worms!

HEIRLOOM VEGETABLES & SEED SAVING

By Mike Davis & Mike Kiessel

Why save seed?

       Save money

       Reduce overall vulnerability to major pest/pathogen events

 Maintain diversity of varieties, preserve “heirlooms,” access to favorites

             Six companies à most seed sales

             Most Americans get to taste ~1% of the vegetable varieties grown in US 100 years ago

 Maintain genetic diversity, which can increase only through mutations

             Enable adaptation to local conditions, climate change, etc.

             Enable development of new cultivars or recovery of “lost” ones

How can I support plant diversity?

       Good:   Buy “heirloom” seed from responsible seed companies

       Better:  Buy seed from Seed Savers Exchange or Exchange members

       Best:    Also practice home seed saving and share seed with others

See www.seedsavers.org, Heritage Farm, Decorah, Iowa

      ~25,000 “heirloom” varieties preserved

       Yearbook: ~13,000 varieties available

       Catalog: ~600 vegetable varieties in inexpensive packets

Also check out the US National Gene Bank at Ft. Collins, Colorado, and the Svalbard Global Seed Vault, Norway.

What seed should I save?

       Open pollinated* varieties (not hybrids)**

       Favorites—save what you want to grow

       Seed selected from healthy, productive plants that show adaptation to your soil and climate conditions

       Easy types for beginners: tomatoes, peppers, eggplants, beans including soybeans, peas, & leaf lettuce

* Open pollinated: “normal” pollination involves a mixture pollen from related and unrelated lines of plants’ or: pollinated by natural means.  Also defined in some sources as pollination by natural means, e.g., insects, wind, etc., rather than by man, but the seed saver often acts as a pollinator of open pollinated varieties.

** Hybrid: the progeny of two different inbred lines of plants (lines previously self-pollinated or pollinated by others of the same variety)  Hybrids do not normally grow “true to type” but can be “stabilized” through persistent selection over time.

Hybrids	“Heirlooms”
Noted for “hybrid vigor”     - Disease resistance     - Growth rate	More choices     - Variety in diet     - Long-term food safety
Many bred for storage & handling, not flavor or nutrition	Typically better flavor; often better nutrient content
Wider adaptation permits sale of fewer varieties	Many better adapted to local growing conditions
Many have shorter growing seasons, higher yields	Usually cheaper: require less energy to  produce
New seed must be hybridized every year	Seed can be saved, “old favorites” preserved

What do seed savers need to know?

•          How to raise plants for seeds

–   Growth cycles determine planting & harvest times

–   Flower characteristics and pollination processes determine isolation requirements and methods

–   Isolation: distance, time, physical separation

•          How to collect and process seeds

–   Select rogues out, diversity in

–   For most: dry

–   Thresh, clean, winnow, and screen

•          How to store seeds (Usually cool and dry)

•          How to test germination

•          How to start seeds

•          Keep records!

Some Veggie History

Natives of the Americas

- Beans, grown 7000 years ago, Columbus àEurope, Passamaquoddy Indians gave to settlers in 1700’s

- Corn (Maize), Andes Mts, grown 4000 years ago, Columbus learned of it 11/5/1492

- Potatoes, Andes Mts, grown in New England by 1719

- Pumpkins/Squash, grown 6000 years ago, IndiansàPilgrims; summer squash to Atlantic coast in the 1600’s

- Tomatoes, Andes Mts, long thought poisonous, but Jefferson grew in 1781, not popular until 1840’s

 Natives of Europe including the Mediterranean region

            - Beets, Southern Europe & N Africa , Germany 1500’s,

            - Cabbage, Mediterranean; Germany, Denmark (hard-head varieties); CartieràCanada 1541

            - Lettuce, Eastern Europe, Italy; popular in Roman Empire, ColumbusàAmericas

            - Parsnips, Eastern Mediterranean, grown at Jamestown & Massachusetts colonies, popular by 1820’s

            - Turnips, Greece, Roman Empire; CartieràCanada 1541

Natives of Asia

            - Carrots, to Europe by 1500’s, grown at Jamestown, Plymouth; “Long Orange” selected in Netherlands, 1620

            - Cress, W AsiaàEngland by 1500’s; American settlers’ children grew on windowsills, put on buttered crackers

            - Cucumbers, India, ColumbusàAmericas, grown at Jamestown, Plymouth colonies

            - Onions, Middle Asia, eaten by builders of pyramids; SpanishàAmericas

            - Peas, Middle Asia & Eastern Europe, first used dry, green use: France, circa 1600; Columbus planted in West Indies; used by colonists as “split peas” until 1700’s

            - Radishes, China, Common food in Egypt, Roman Empire, Ancient Greece; Columbus brought Black Spanish to Americas

Massachusetts Colony settlers’ children:               Pilgrim:

     Bean porridge hot, bean porridge cold,             “We have pumpkins at morning and pumpkins at noon,

     Bean porridge in the pot, nine days old               If ‘twere not for pumpkins we’d soon be undoone.”

Some Definitions

Flower as shown: “perfect”

Flower having pistil but not stamen: female or “pistillate”

Flower having stamen but not pistil: male, or “staminate”

  

“Top Ten” Families & Some Examples of Heirloom Varieties

Solanaceae [Capsicum: pepper   Solanum: tomato *]

    Tomato: Solanum or Lycopersicon lycopersicum

•           Flower: perfect

•           Cycle: annual

•           Pollination: inbreeding; most self-pollinate, some (e.g., potato-leaved tomato varieties, below) have protruding styles and cross-pollinate

•           Mechanism: agitation (e.g., wind)

•           Isolation: unnecessary for most

•           Notes:

–   Fermentation of seed gel improves results

–   Seed remains viable up to 10 years if frozen

Pepper: Capsicum annuum

•          Flower: perfect

•          Cycle: tender perennial grown as annual

•          Pollination: inbreeding; self-pollinating but with frequent cross-pollination

•          Mechanism: agitation (self); insects (cross)

•          Isolation: intermediate—cage or bag if isolation of variety is impractical

•          Notes:

–   Rinse, dry until brittle

–   Use caution with hot varieties

(Eggplant is similar)

King of the North Sweet Pepper

Liliaceae (family name per USDA, formerly Amaryllidaceae or Alliaceae) [Allium: onions, leeks, chives… asparagus]

    Common seed-producing onion, Allium cepa, cepa group

•          Flower: perfect

•          Cycle: biennial

•          Pollination: inbreeding; cross-pollinate, cannot self-pollinate

•          Mechanism: insects

•          Isolation: intermediate; suggest alternate day caging

•          Notes:

–   Dry bulbs, overwinter, replant in spring

–   Harvest seed when beginning to dry

–   Seed keeps only ~1 year

–   May cross with bunching onions (Allium fistulosum)

Leek, Allium ampeloprasum

•          Flower: perfect

•          Cycle: biennial

•          Pollination: outbreeding; cross-pollinate,  cannot self-pollinate

•          Mechanism: insects

•          Isolation: intermediate; suggest alternate day caging or caging with introduced pollinators

•          Notes:

–   May produce “pearls” if overwintered in ground

    Garlic, Allium sativum

            Notes:

–   Reproduced by dividing individual cloves from bulbs in late summer and planting in autumn

–   Hardneck varieties form numerous bulbils in top clusters reminiscent of seedheads.  The bulbils may be planted and can produce full-size bulbs after 2-3 years.

–   For larger bulbs, however, the curled stalks known as scapes should be removed.  These are delicious in stir-fries!

Spontaneo Heirloom, Northern Italy, Early 20th Century

Brassicaceae [Brassica: cabbage, mustard, turnip…   Others: radish, cress…]

    Radish: Raphanus sativus

•          Flower: perfect

•          Cycle: annual (most)

•          Pollination: outbreeding; cross-pollinate, most cannot self-pollinate

•          Mechanism: insects

•          Isolation: intermediate; suggest alternate day caging or introduced pollinators in cages

•          Notes:

–   Cross with other radishes including wild

–   Edible seed pods

    Cabbage: Brassica oleracea, Capitata group

•          Flower: perfect

•          Cycle: biennial

•          Pollination: outbreeding; cross-pollinate,  normally self-incompatible

•          Mechanism: insects

•          Isolation: intermediate; suggest alternate day caging or introduced pollinators in cages

•          Notes:

–   Overwinter, replant, cut open top of heads

–   Can cross with broccoli, Brussels sprouts, cauliflower, collards, kale, kohlrabi

Late Flat Dutch, 1840's

Broccoli: Brassica oleracea

•          Flower: perfect

•          Cycle: biennial, but some can mature same year

•          Pollination: outbreeding; cross-pollinate,  normally self-incompatible

•          Mechanism: insects

•          Isolation: intermediate; suggest alternate day caging or introduced pollinators in cages

•          Notes:

–         Challenging; require vernalization; flowering induced by long days

–         Can cross with cabbage, Brussels sprouts, cauliflower, collards, kale, kohlrabi

Here are two favorites: Purple Top White Globe turnip, from 1885; and De Cicco broccoli, from 1890:

Compositae [Several genera: lettuce, sunflower…] (formerly Asteraceae)

    Lettuce: Lactuca sativa         

•          Flower: perfect

•          Cycle: annual

•          Pollination: inbreeding; self-pollinate

•          Mechanism: mainly internal: style emerges through anther tube

•          Isolation: easy; can cage for absolute purity

•          Notes:

–   Some crossing between varieties and with wild lettuce

–   Seed stalks of head-forming lettuce may have difficulty in emerging from heads

–   Loose-leaf varieties are easier

                                     Black Seeded Simpson, 1860's

Chenopodiaceae [Several genera: beet, formerly included spinach]

    Beet: Beta vulgaris    

•          Flower: perfect

•          Cycle: biennial

•          Pollination: outbreeding; cross-pollinate

•          Mechanism: wind

•          Isolation: demanding (miles!); suggest growing only one variety

•          Notes:

–   Cross with Swiss chard, sugar beets, etc.

–   Require vernalization from about 45 degrees

Cucurbitaceae  [Cucurbita: squash   Cucumis: cucumber]

    Squash: Cucurbita maxima, C. mixta, C. moschata, C. pepo  

•          Flower: monoecious

•          Cycle: annual

•          Pollination: cross-pollinating, outbreeding; can suffer inbreeding depression if isolated

•          Mechanism: insects

•          Isolation: intermediate

•          Notes:

–   All “pumpkins” are squash

–   Most “summer squash” are C. pepo

–   Suggest growing one variety from each species

–   Easy to hand-pollinate but timing is critical

–   Cucumbers (Cucumis sativus): similar, but ferment seeds

–   Muskmelon (Cucumis melo): like cucumber, but more difficult to hand pollinate

–   Cucurbita Species (“Squmpkins”)

                           C. maxima

                                    “Pumpkins”: Big Max, Rouge vif d’Etampe (Cinderella), California White, Small Orange, Amish Pie, many others

                                    “Squash”: all banana, buttercup, Hubbard

                                    “Gourds”: turban

                     C. mixta

                                    “Pumpkins”: Potato

                                    “Squash”: most Cushaw, Sweet Potato, all wild Seroria, others

                                    “Gourds”: all silver seeded

                    C. moschata

                             “Pumpkins”: milk, most Seminole

                                     “Squash”: all butternut, Golden Cushaw, all cheese, Seminole ‘acorn’

                    C. pepo

                             “Pumpkins”: New England Pie, Amish Field Pie, Cinderella (not Rouge vif d’Etampe), Baby Bear, Cow, Old Timey Flat, Omaha

                             “Squash”: all acorn, crookneck, scallop, spaghetti, vegetable marrows, zucchini

                                     “Gourds”: many including Sweet Dumpling

Fabaceae [Phaseolus: common, lima, runner bean   Pisum: peas   Other: fava, soybean…] (formerly Leguminosae)

    Common Bean: Phaseolus vulgaris

•          Flower: perfect

•          Cycle: annual

•          Pollination: self-pollinating, inbreeding; insects can cause some crossing between varieties

•          Mechanism: mostly internal before flowers open; mostly wind, some insect tripping

•          Isolation: easy

•          Notes:

–   Crossing effects show up only in succeeding generations—keep previous year’s seed

–   SSE maintains over 2000 varieties

Scarlet Runner Bean: Phaseolus coccineus

•          Flower: perfect

•          Cycle: tender perennial grown as annual

•          Pollination: self-pollinating, inbreeding, but can outbreed considerably within species

•          Mechanism: requires tripping by insects (or by hand)

•          Isolation: intermediate, but not very commonly grown in North

•          Notes: 

–   Some varieties day-length sensitive

–   Can winter over in damp sand

–   Often listed with flowers

    Pea: Pisum sativum

•          Flower: perfect

•          Cycle: annual

•          Pollination: self-pollinating, inbreeding; internal, mostly before flowers open

•          Mechanism: agitation mostly wind; bees can open flowers and cross-pollinate

•          Isolation: easy

•          Notes:  Pull plants when seeds rattle

    Soybean: Glycine max

•          Flower: perfect

•          Cycle: annual

•          Pollination: self-pollinating, inbreeding; internal (anthers dehisce before flowers open)

•          Mechanism: agitation mostly wind

•          Isolation: easy

•          Notes: Dry on plants

Apiaceae (aka Umbelliferae [Various genera: carrot, celery, dill, parsley, parsnip]

    Carrot: Daucus carota

•          Flower: perfect

•          Cycle: biennial

•          Pollination: outbreeding; cross-pollinate, cannot self-pollinate

•          Mechanism: insects

•          Isolation: difficult

•          Notes:

–   Cross with wild Queen Anne’s lace (white root color is dominant)

–   If caged, hand pollinating must be done every day for 2-4 weeks

–   Dig & store over winter, or winter over in ground with heavy mulch (also parley, parsnips)

My New “Shelf Decoration”

(Nantes carrot wintered over under straw, photo May 1)

Amaranthaceae [Amaranth, spinach]   (Family is an example of “Botanical disarray”)

    Spinach: Spinacia oleracea (formerly listed in family Chenopodiaceae)

•          Flower: most dioecious

•          Cycle: annual

•          Pollination: outbreeding; cross-pollinate

•          Mechanism: wind

•          Isolation: demanding; cage many plants together

•          Notes:

–   Very fine pollen

–   Seed heads shatter easily

–   Harvest of some outer leaves OK

    Amaranth (Grain & Vegetable): Amaranthus tricolor

•          Flower: monoecious

•          Cycle: annual

•          Pollination: self; inbreeding, some outbreeding; can cross-pollinate

•          Mechanism: wind, some insects

•          Isolation: fairly demanding

•          Notes:

–   Research incomplete

–   Very fine pollen

–   Subject to inbreeding depression; bag or cage several plants together

–   Shake if protected from wind

Poaceae [Zea mays (corn…), sorghum]

    Corn (Maize): Poaceae (Gramineae) Zea mays

•          Flower: monoecious

•          Cycle: annual

•          Pollination: outbreeding, crosses readily with any other corn variety

•          Mechanism: wind

•          Isolation: demanding; long distance and/or time isolation, or bagging & hand pollinating

•          Notes:

–   Susceptible to inbreeding depression

–   Hand pollinating easy to do with commercial shoot and tassel bags

Recommended Reading

The Field and Garden Vegetables of America, Fearing Burr, Jr., 1863.  Great insight into how vegetables have changed through the years.

Seed to Seed, Suzanne Ashworth, Seed Savers Exchange, 2002.  THE book on seed saving for the beginner.

Growing Garden Seeds, Robert Johnston, Jr., Johnny’s Selected Seeds, 1983.  A concise and inexpensive introduction.

Heritage Gardening, 4-H 1279 Bulletin, The MSU Museum.  American Association for State and Local History 1985 award winning publication, available online.

The Wisdom of Plant Heritage: Organic Seed Production and Saving, Bryan Connolly, NOFA, 2004

The Complete Guide to Saving Seeds, Robert Gough & Cheryl Moore-Gough, 2011

“Seed Starting Made Simple,” Mother Earth News, Feb-March 2012, pp 35-37 (available online)

The New Seed Starter's Handbook, Nancy Bubel, 1988

Root Cellaring, Mike & Nancy Bubel, 1991.  How to save biennial root vegetables for consumption and/or growth for seed production the following year—and more.

Publications by Seed Savers Exchange, Inc.  See www.seedsavers.org.

http://www.treehugger.com/natural-sciences/quote-of-the-day-jonathan-porritt-on-saving-our-seeds.html

http://www.seedsave.org/issi/issi.html

http://www.howtosaveseeds.com/index.php

http://umaine.edu/publications/2750e/

HARDENING OFF WARM-WEATHER PLANTS

by Mike Davis

Finally!

In my first post, I promised to write something about hardening plants off (getting them accustomed to outdoor conditions) before transplanting outdoors.  Well, this year has been an adventure, but well worth it. Here are some Gypsy and Snapper sweet peppers just after planting.  I'll wait until the soil warms up a bit more before mulching with straw.

I like to start exposing plants to outdoor conditions at least a couple weeks before planting. Having only one small cold frame to use for hardening off my plants, I was constrained to frequent moving of trays of plants back and forth between their too-comfortable indoor quarters under fluorescent lights and various locations outdoors depending on weather conditions--and such weather we've had! Hardening off a plant might be compared with working out in the local gym.  Muscles (and stems) grow strong when stressed; "no pain, no gain," as the saying goes.  But too much pain can cause setbacks, and we've had a couple of those.  Snow on May 11?!

 Here are some of my tomatoes and peppers on my deck, partially protected from wind an bright sun on a breezy, drying day.

Conditions to which plants need to become acclimated include:

      - Direct sunlight, several times more intense than that provided by my fluorescent lights with limited natural window light.  Exposure times on sunny days are short at first, just a couple hours each day, then increasingly longer until all day in the sun causes no ill effects.

      - Varying amounts of moisture including drying out of soil near the surface.  As I start setting plant trays outdoors, I continue bottom watering using deeper containers to "teach" roots to reach downward for their nutrients; and I progressively increase times between watering, allowing plants to wilt a bit before watering.

      - Wind.  Even before beginning exposure to outdoor conditions, I use a fan for air circulation in my seed starting area.  Mike Kiessel taught me also that it helps to stroke the plants by hand occasionally.  Initially on windy days (typically with gusts above about 10 mph), I provide some shelter from the wind.  To prevent my tall cups from upsetting in their trays, I use plywood tray covers with holes cut with a hole saw. The slot cut in the end of the cover makes it easy to add water to the trays as needed, continuing the practice of mostly bottom watering.

 At last, after a heavy frost on June 3, I got my ten tomato varieties in the ground June 4, peppers on June 8.  This is when growing the plants in latte cups, etc., has another advantage.  To prevent cutworm damage and preserve my variety labels, I simply cut off the top half of each cup and use it as a cutworm collar.

Here are some of the tomatoes just after planting, happy in their new surroundings.  I can almost taste those pink slicers now!

SEED STARTING EXPERIENCES

by Mike Davis

Each year at about this time, quite a few magazine articles on starting vegetable seeds indoors are readily available.  I’m sure if we follow the directions in almost any of these, our odds of growing usable plants will be quite good.  My intent here, then, is mostly to make those odds better—disaster avoidance—and hopefully to save a few dollars in the process.  My methods are not the only good ones—they’re simply what I do; there will always be exceptions to my “rules.”  It’s "food for thought" before trying for food in the garden that I’m after.

First, what plants do we want to start?  Here’s are list of those we'll need to grow or purchase to set outside as plants, some we can safely plant outdoors as seeds, and a good many that are truly optional.

Key:

Blue - hardy or "half-hardy"

Red - tender, frost-sensitive

* Asterisk - fragile roots, exercise care

Ones from the center column I start at least partly indoors: basil, broccoli, cabbage, dill, kale, & parsley.

I buy most of my onions as plants (not sets); I don't usually grow Brussels sprouts or cauliflower.  I'm trying leeks & sage indoors this year—they seem to be doing well.

Plastic Cups & Newspaper "Pots"

OK, we have our seeds.  What else do we need?  Mostly some appropriate containers, plant starting mix, a good source of light, and ample patience.  Let’s start with clean, sterilized containers.  Some people ask about using egg cartons: I don’t—they’re too shallow.  I use a variety of things, including some dedicated cell trays (but I’ll never buy any more of those), old recycled plug- or cell-type nursery tray containers, used paper and plastic cups of various sizes, and “pots” made from the local newspaper.  All containers must allow bottom drainage; if I’m using cups to start seeds, I use a pencil (one of my favorite tools) dipped in the bleach solution to poke a few holes in the bottoms.  I don’t recommend “peat pots” for several reasons: they cost too much; they’re made from non-sustainable sphagnum peat; and they tend to wick moisture away from plants’ root zones.

One thing all of my containers except the newspaper ones have in common is that I’m careful to sterilize them to prevent damping off (fungal) disease.  It can cause plant stems near the soil surface to simply collapse.  The containers get washed, then thoroughly rinsed in a sodium hypochlorite bleach solution: add 3 ounces of bleach to enough water to make a quart (and use hand and eye protection).  Special care is needed in the case of reused nursery containers because any residual soil may contain the offending fungi.  I haven’t had a problem with using the newspapers.

Coir Brick, 4 x 8 x 1.25 inches
Expands to 4 quarts when water is added

Next we’ll need to add some premoistened “soil,” in this case, a  light seed-starting medium or “soilless mix.”  For many years, I used a very good commercial one that’s a mix of peat, vermiculite, perlite, and a little compost.  I won’t buy more of that because sphagnum peat is clearly non-sustainable, so from now on I’m mixing my own.  I avoid typical “potting mixes” because most of those contain added fertilizers of various types.  New seedlings don’t need that fertilizer, and the extra nitrogen it provides can speed the growth of the fungi that cause damping off.  I’m experimenting (so far so good!) with either coir (shredded coconut hulls) or milled sphagnum moss (not peat) with some perlite and vermiculite mixed in, and with coir alone.  I’ll probably continue with the coir mix, as it shows an extremely high water retention capacity, is much less expensive than the sphagnum, and is sold in compact “bricks,” so shipping charges are reasonable.  I start by moistening the mix with water (preferably lukewarm, just moist (not soaking wet), letting it settle for an hour or so for the water to be fully absorbed, then gently tamping it down into the containers to fill any large gaps.  The containers are then placed in flat-bottom, waterproof trays and are ready for planting.

Seed Starting Area With Two Heat Mats
The one on the left is thermostatically controlled.

Let’s talk specifically about  tomatoes for a moment; they’re the most commonly grown of the plants that are almost always started indoors, and just a little more complicated to grow than some others.  Since tomato seeds should be planted about 1/4 inch deep, I use a sterilized pencil to make shallow indentations about 1/8 inch deep in the mix, usually three per cup or cell.  I use sterilized tweezers to drop a seed in each indentation and gently cover and tamp down the mix over the seed.  Then using a latex glove, I sprinkle about 1/8 inch of dry milled sphagnum moss (again, not peat) over the top, then set the tray it in a warm spot.  I have two commercial heat mats for that purpose, but these are not essential; I started plants without them for decades.  Setting the tray on top of a fluorescent “shop light” works well.  One of my heat mats is thermostatically controlled; I set the temperature for about 80 degrees F; I elevate the tray above the other mat to achieve that 80 degree level, using a small thermometer to check the temperature fairly often.  I carefully label the containers and keep records of the varieties and their progress. 

Tray with Transparent Cover

Milled Sphagnum Moss

I sometimes use transparent tray covers or even plastic food wrap to cover seed containers when it’s not convenient for me to be there to mist very small seeds at least twice a day until they begin to show growth.  However, covering offers an ideal environment for fungal growth.  A thin layer of milled sphagnum can be helpful in this regard—think of it as a mulch for about-to-emerge seedlings.  I don’t know of a mechanism other than that it dries quickly on the surface but retains water within its bulk, but the milled sphagnum clearly has an antifungal effect.

As soon as the first tiny plants begin to emerge, I remove the tray from the warm area, place it under fluorescent lights near a window in a room that’s kept in the 60-65 degree range.  The lights should be in a configuration allowing adjustment of height above the plants, and should be kept no more than an inch above the plants.  Some folks say one must have special broad-spectrum “grow-lights” to grow good plants; this is not the case.  The only instances wherein the grow-lights are really needed are those involving growing plants to a flowering stage, or in special situations where close proximity between the bulbs and the plants cannot be maintained.  Standard cool-white bulbs are fine; using one cool-white and one warm-white bulb in a fixture may provide more visual appeal.  Even as close as an inch from a fluorescent bulb, the light intensity is much less than outdoor light on a bright day.  I grow my plants near a window to take advantage of the extra light, and I leave the lights on for about 16 hours each day.  My meter shows the light level on my plants an inch away from the fluorescent tubes is between 15 and 20% of that provided by full sun; it’s overcast today, and the outdoor level at noon is about 8-10% of full sun.

Plants Under Fluorescent Lights

I set a small fan nearby to maintain a constant air flow, and begin bottom watering.  This encourages strong root growth and allows the surface of the planting mix to remain dry.  To do this, I simply remove the cups or cells from the tray and place them in a dedicated watering tray containing about a half inch of not-too-cold filtered water; I sterilize that tray before each use.  I leave the plants there for a while to allow water to wick up through the mix.  Depending on the mix and the containers, that can take from a few minutes to a half hour or so; I check to be sure the mix is moist up to near the top before returning the plants to their dry trays.

As soon as the plants develop their first “true” leaves (versus seed leaves), I give them their first dose of fertilizer.  I do this by adding a diluted mix of fish emulsion (5-2-2) with a little organic seaweed concentrate (0-4-4) to their water about once each week.  I start with concentrations about 1/4 of those recommended on the labels and slowly increase to the recommended amounts.  There seems to be some evidence that the fish emulsion makes damping off diseases less likely to occur at this stage.

In the case of tomatoes, when the second set of true leaves are developing, I transplant to larger containers, usually 20-oz latte cups, of which I always seem to have a surplus.  When handling plants, I use sterilized vinyl gloves, cleaning and moistening with bleach solution after each use. Again, I make sure there are a few pencil-size holes in the bottoms.  For this purpose, I use a different type of growing mix, one with up to 25% compost added.  I start by scooping a little of the mix into the bottom of the cup, then carefully moving the plant with as much of its original mix as possible intact.  A long-tined meat fork is a handy tool for this process.  If the roots appear to be at all bound along the edges of the root ball, I loosen or even cut them a bit to help their transition into their new environment.  I then fill in around the roots and the stem up to leaf level with the new, richer growing mix; I often remove all but the first two true leaves at this time so that most of the stem will be buried; it will soon extend new roots wherever it’s below the surface.  I try to remember to label each new container as I proceed; last year, I was amazed that one of my “cherry tomato” plants grew large pink slicers.

Now it’s just a question of keeping plants watered and fed a little, provided with plenty of light, and watching them grow until a couple weeks before outdoor planting time.  Then it will be time to get them accustomed to outdoor conditions…but that’s a project for a later post.