Organic Compost Tumblers by Christina Orr (+506.8342-6817)
What is compost?
• Composting is a biological process by which micro-organisms convert organic material into a dark, rich humus soil-like material, called compost. It is the same natural process that produces the dark humus layer on the forest or jungle floor. Composting differs only in the intentional creation of conditions that result in more rapid decomposition of organic material than what would naturally occur in nature. Composting has been common practice for centuries; modem composting differs only in application of scientific knowledge, which accelerates the decomposition.
1. Most Costa Rican home owners and gardeners have long understood the value of this rich, dark, earthy material in improving the soil and creating a healthful environment for plants. Compost is one of nature’s best mulches and soil amendments, and you can use it instead of commercial fertilizers. Best of all, compost is cheap. Using compost improves soil structure, texture, and aeration and increases the soil’s water-holding capacity. Compost loosens clay soils and helps sandy soils retain water. Adding compost improves soil fertility and stimulates healthy root development in plants. The organic matter provided in compost provides food for micro-organisms, which keeps the soil in a healthy, balanced condition. Nitrogen, potassium, and phosphorus will be produced naturally by the feeding of micro-organisms, so few if any soil amendments will need -to be -added.
2. Understanding how to make and use compost is in the public interests since the problem of waste disposal in Puerto Viejo Talamanca, Costa Rica is at a crisis level. We are being forced to deal creatively with our own organic waste. About one third of the space in landfills is taken up with organic waste from our yards and kitchens, just the type of material that can be used in compost. With a small investment in time, you can contribute to the solution to a community problem, while at the same time enriching the soil and improving the health of the plants on your property.
• The Compost Decomposition Process:
Compost is the end product of a complex feeding pattern involving hundreds of different organisms, including bacteria, fungi, worms, and insects. What remains after these organisms break down organic materials is the rich, earthy substance your garden will love. Composting replicates nature’s natural system of breaking down materials on the forest floor. In every forest, grassland, jungle, and garden, plants die, fall to the ground, and decay. They are slowly dismantled by the small organisms living in the soil. Eventually these plant parts disappear into the brown crumbly forest floor. This humus keeps the soil light and fluffy.
Humus is our goal when we start composting. By providing the right environment for the organisms in the compost pile, it is possible to produce excellent compost. We usually want to organize and hasten Mother Nature’s process. By knowing the optimum conditions of heat., moisture, air, and materials, we can speed up the composting process. Besides producing more good soil faster, making the compost fluster creates heat which will destroy plant diseases and weed seeds in the pile.
Compost is an oxygen requiring process, because the microorganisms and other biological decomposers responsible for compost consume oxygen. In addition to compost these microorganisms produce: Heat—C02—H20 (by-products of compost). The heat that is produced raises the temperature of the composting material (you can feel it with your hand). The oxygen that is consumed during the process must be continually replaced (by turning the tumbler), or else the condition will change to anaerobic condition (without oxygen) Anaerobic decomposition is slower than aerobic decomposition,. Anaerobic produces little heat and creates odorous byproducts. Aerobic decomposers provide the most rapid and effective composting. They thrive at 02 levels greater than 5%. (Fresh air is aprox. 21% 02). The challenge for the composter is to minimize anaerobic decomposition by creating and maintaining conditions that favor the desired decomposers.
Who are the favored decomposers and bow do we get them in our -compost pile? Food and liquid that we put in the compost bin is the medium that the decomposers enter. Different decomposers. prefer different organic. materials. and different environmental conditions. So, it’s good to have a diverse population, as changing conditions during the composting process lead to an ever-changing ecosystem of decomposer organisms.
1. Most abundant are the microorganisms that are naturally occurring amongst us, namely bacteria, which are the workhorse of the decomposition. Bacteria prefer moist. environment and first attack the most decomposed material such as green vegetation, fruit. and food scrap and manure,
2. Second, are the Actinomycetes and fungi (yeast, mold, hongo) that attack the most resistant material and are particularly good with woody material and dry conditions.
3. Thirdly, the secondary decomposers or “macro-organisms” that play a significant- and beneficial role as the compost matures. These include nematodes, flatworms, earthworms, beetles, ants, fly larvae, -grubs, sow bugs, centipedes, . All of -these microorganisms are curing or maturing off the pile, by breaking particles into smaller pieces, mixing and transporting materials, converting materials, into forms. that microorganisms can further digest and add their own by-products and cell tissue to the compost.
What to compost??:
Given optimum conditions, compost can be finished in as short as two weeks. This all
depends on the proper mix of air, water, and raw materials, namely the Carbon to nitrogen ratio (C:N).
What is Carbon? All your brown stuff:
1. dry leaves,
2. sawdust and untreated wood shavings (excellent for nitrogen materials because of the high carbon content)
3. Cardboard (shred into small pieces)
4, rice hulls
5. Cornstalks and corn cobs (Best if shredded and mixed well with nitrogen rich materials),
6, Dryer lint: Compost away!
7. wood ash, ashes from coal or charcoal (yes, but sparsely),
8. Newspaper (shred it so it breaks down easier),
9. Pine needles and cones
What is Nitrogen? All your “green” stuff:
1. fruit (and fruit peels, rind and seed),
2. vegetable trimmings and tops,
3. tea leaves and tea bags,
4. Algae, seaweed and moss,
5. Bird droppings,
6. Coffee ground and filters,
8. Hair (scatter so it isn’t in clumps),
9. wool waste,
10. Manure (horse, cow, pig, sheep, goat, chicken, rabbit) NO CAT OR DOG OR HUMAN
ii. Milk, cheese, yogurt,
12. yard clippings, spent flowers, Weeds (careful, better to dry them on pavement then add).
• Things to avoid in your compost Pile:
1. All carnivores manure including cat litter.
2. Diseased plants, herbicide treated plants, and weeds gone to seed
3. Meat and Bones and fish scrap
5. Fat and Grease, Oil, Butter (Mayonnaise, salad dressing, sour cream, and peanut butter)
Typical C:N Ratios
Dry leaves 60:1
Corn stalks 60:1
Shrub trimmings 50:1
Waste paper 400:1
Wood (sawdust, shavings) 500:1
Grass Clippings 17:1
Kitchen scrap 15:1
Vegetable culls 12:1
Cattle manure 18:1
• RECOMMENDED CONDITIONS FOR COMPOSTING
|CONDITION||REASONABLE RANGE||PREFERRED RANGE|
|PARTICLE SIZE||1/8-1/2 IN.||VARIABLE|
Factors Affecting the Composting Process:
1. Aeration both the porosity (space between the particles) and the frequency of turning
2. Moisture: enough to maintain chemical activity but not soggy enough to hinder aeration; ideally, 40%–60%. Squeeze test: compost should be damp when squeezed tightly in the hand buy not dripping. If you can’t feel moisture, then it is too dry.
3. C:N ratio: microorganisms use C compounds as an energy source and ingest N for protein. Therefore, the ideal 30C to 1N (by weight) for microorganisms to decompose organic matter quickly. However, a range for good compost in a reasonable lime with low to no odor, is 20C:1N to 50C to 1N. Since we don’t naturally get the perfect ratio, we have to mix or balance the ratio by what percentage of organic materials we add. This proportion is known as the recipe. It is impractical to be precise on a small-scale use, therefore we need to predict our C:N ratio from the ingredients. (For example, 1-3 volumes of brown dry leaves to 1 volume of Greens (grass clippings) often produce a C:N ratio of 30:1 to 50:1 range.
4. Surface area or particle size: Chopping, shredding, and cutting up into smaller pieces speeds up the decomposition; 1/8” to 2” is ideal.
5. Degradability: not all organic matter decomposes equally; plant greens are the fastest with woody to raw the slowest.
6. Temperature: hot vs. cold.
7. Time depends on method, turning, moisture and the C:N ratio.
Why I like compost tumblers
I. Compost tumblers are nice looking. Neighbors and family members won’t complain about an ugly homemade compost pile or bin.
2. Compost tumblers are pest resistant. Dogs won’t get into your compost, or squirrels or raccoons or rats.
3. Compost tumblers are easy to keep aerated. You don’t need a pitchfork, or a compost turning tool. You just turn the composter or flip it over and your compost gets mixed.
4. Compost tumblers stay closed up. In hot weather, the compost stays damp longer and doesn’t dry out. In wet weather, the compost doesn’t get too soggy. Any smells stay inside the compost tumbler (although compost shouldn’t smell bad if you are doing it right).
5. Compost tumblers are simply more fun! Let’s face it, it’s kind of fun to go out and turn the compost when you keep it in a tumbler. It feels like you’re accomplishing something, yet it isn’t hard work.
6. Compost tumblers make compos faster. Honestly, if you make a giant pile of compost and keep it well stirred and aerated, you can get compost from a pile just as fast. But who has time for that? Using a tumbler makes the whole composting process easier.