Plant Answers

Composting

This is the time of year when leaves begin to fall—hence the season is called fall—making lawns rather unsightly. Our flower beds are beginning to fade because of environmental adversities. Whatever the case, we need to gather the leaves and discard plant rubbish.

Is this debris trash or treasure? It can be treasure if you don't dispose but rather, compost! A ton of leaves is worth over $10 in nutrients alone. Leaf mold has a miraculous ability to hold moisture. Subsoil can hold a mere 20 percent of its weight, good topsoil will hold 60 percent, but leaf mold can retain 300 to 500 percent of its weight in water. Leaves and plant material can be used to improve growing conditions for the next season. Composting is the "natural" way of doing things. Nature has been successfully composting for millions of years.

Compost is a mixture of decomposing and rotting debris that can be used to add fertilizing elements back into the soil. Composting is a process that returns plant and animal matter back to the soil and completes the natural life cycle. This cycle began when you planted the seed. As the small plant of the seed grew, it took nutrients from the soil to make cells and metabolites. As the plant grew larger, more minerals were required and accumulated. When the plant dies, it is decomposed and the "borrowed elements" returned to the soil. Thus, the cycle is completed. At this time of the year you decide whether this natural recycling system will benefit your soil or the garbage dump.

The advantage of using organically?released fertilizer elements is mainly one of economics. They are free! Gardeners should realize that organically?released fertilizer elements do not differ in any form or fashion from those fertilizer elements obtainable from other sources. The organic combinations of elements must be reduced to some soluble inorganic form before being absorbed by plants again. These inorganic forms are also found in commercial fertilizers. Armed with this information, one can readily recognize the fallacy in the claim that vegetables and other food products that have been fertilized with chemical fertilizers are somehow harmful to human health and are not as tasty as those in which the same elements were supplied from compost or other "natural fertilizers." The main advantage, other than an economical fertilization technique, is that compost added to the soil will improve soil tilth and its ability to hold moisture. These factors will encourage optimum plant growth and maximum yields if proper cultural practices are followed.

Basic items that can be used for composting include:

GRASS CLIPPINGS ??Mix green, fresh clippings with soil or
or dry plant material such as leaves. Be sure that large sprigs that could root and propagate themselves are eliminated. A thick layer of fresh clippings usually compacts when it settles. This prevents air from entering the pile and slows or prevents the composting process. To prevent this problem, add and dry thin (no more than 3 inches deep) layers of green grass clippings. Also, denser organic materials can be intermixed with grass clippings to prevent compaction. Grass clippings are relatively high in nitrogen and make good compost.

DRY LEAVES ??These are plentiful in the fall and often can be found in bags by the curb waiting for the garbage collector. Most leaves compost faster and more thoroughly if shredded before adding to the pile. If you do not have a shredder, place the leaves in a row on your yard and cut them up with a rotary lawn mower. Rake the chopped leaves and add them to the compost pile. Shredding greatly increases the total surface area of a material. The conversion of raw organic material into colloidal humus is accomplished by a series of fermentations. These fermentations consume the plant residues like a living fire. The finer the particles, the faster they will be consumed. The faster a compost is made the better it is because there is less time for the dissipation of valuable gases and the leaching out of essential elements.

SAWDUST ??Always compost sawdust before adding to a garden soil. It is low in nitrogen and thus breaks down slowly. Add extra nitrogen to speed breakdown and decomposition.

KITCHEN SCRAPS ??Fruit and vegetable trimming and leftovers are good items for the compost pile. DO NOT use animal products such as grease, fat and meat trimmings since they break down very slowly, attract rodents and other pests and have an unpleasant odor. No one appreciates a rat sanctuary or a buzzard roost in a neighbor's compost area! Offensive odors will also develop if the compost piles become soggy or anaerobic (lack of sufficient oxygen).
GIN TRASH ??This makes good compost but be sure that arsenical residues are not present. Arsenic can carry over in gin trash from cotton defoliants and cause vegetables to grow poorly.

OTHER MATERIALS ??These include sod removed from the lawn, hay, shredded newspaper and hedge clippings. Large twigs break down slowly, so do not use them. Bone meal is a good addition to the compost pile because it is high in nitrogen.

Most people get in trouble with compost piles by making them using only one ingredient. Sometimes, if only one ingredient is used, nothing will happen regardless of additives and the techniques used. It is essential to add some nitrogen?rich material such as fresh or dried manure or commercial fertilizer because the nitrogen in these materials is needed nutrition for the decomposing bacteria.

If a compost pile is properly made and maintained, an excellent composted material should be ready for use in 90 to 120 days. I recommend the "sandwich" composting method. This involves piling layer upon layer of compost material to create a "sandwich" effect.

If possible, choose a site on level ground and near a water source since moisture will be required. Pile an 8 to 10?inch layer of rough brush or twigs on the bottom of your site. This will especially help if you choose not to turn your compost. (Unturned compost will take about 6 to 8 months to decompose.) On top of the twigs, pile 8 to 10 inches of plant material. Add a light sprinkling of high?nitrogen fertilizer or a "natural" fertilizer such as manure, bone meal, or cottonseed meal to this plant material. Apply about 1/2 pound or a cup of high nitrogen fertilizer (21?0?0) for each 10 square feet of a 6-inch thick layer. Covering with clear or black plastic will speed up decomposition due to increase in heat under the plastic. Do not make the covering airtight since oxygen is needed for decomposition. On top of this first layer repeat these layers (omitting the twigs) until the pile is as high as you desire. Try to keep the pile standing; some people build supporting structures or use hardware cloth rather than trust a free?standing pile. Difficulties can arise if the compost pile is too large. The right height is about 5 , because it allows air to penetrate freely, providing the pile is not too wide either (no more than 10 to 12 feet wide at the bottom, generally not less than 5 feet).

Remember to turn and moisten the pile every 2 to 3 weeks to provide proper aeration and temperature. However, do not keep the composting material too wet. Offensive odors will develop if the compost pile becomes soggy or anaerobic (lack of sufficient oxygen). For this reason, piles should be kept moist and open by periodic spading. This will not only reduce odor but will also hasten the decaying process. When the pile begins to work, it will have a hot (160 degrees F.) internal temperature. It is absolutely essential that the compost pile be well ventilated so that there is a sufficient flow of gases between the atmosphere and the interior of the compost pile. The soil organisms that break down the plant residues and convert them into compost are aerobes, i.e., they must have oxygen to live. The composting process will stop if these organisms suffocate and die because lack of oxygen.

The compost will be ready when it smells earthy and has a brown, rich humus look and feel. Some people think the finished product of their composting should be crumbly like old leaf mold. However, for gardening purposes, it is not necessary to allow the material to completely decompose since the final decay can take place in the soil. When compost is added yearly, the soil will become fluffy, fertile, easy to work and hold soil moisture better. Composted organic materials can also be used as an inexpensive iron chelate (a slow?release source of iron) which can remedy the adversities of iron chlorosis, i.e., yellowing plants. Gardeners can make a "synthetic chelate" in their compost piles by mixing 1 cup of iron sulfate (copperas) for each bushel of moist compost. Particles of iron will adhere to the surface of the compost material and will be released for plant-use as the material decomposes while being used as a mulch around plants or when incorporated into the soil.

It is well advised not to use old garden plant debris and wood ashes in compost piles. Old garden plant debris may contain insect eggs and disease spores that may not be completely destroyed by standard composting procedures.

The "standard" composting procedure involves more rotting than composting. The composting procedure generates heat that can pasteurize (kill undesirable pathogens) organic material. However the composting process requires the presence of oxygen that necessitates spading and turning the organic material to allow oxygen penetration. Most of us pile organic material and never turn and aerate it. Thus we rot, not compost. If over-wintered in a compost pile and spread back onto the garden area, pathogen remains could possibly re-contaminate spring crops. Wood ashes are alkaline and, even though containing traces of phosphorus and lots of potassium, are not beneficial. The best place for old plant debris and wood ashes is in the garbage.

The whole point of composting is to produce a beneficial soil additive. Moreover, humus is recognized as an excellent soil conditioner. Besides increasing the soil's water?holding capacity, improving its tilth and aeration, compost also makes plant nutrients already in the soil more available to plants. However, compost is rarely a complete fertilizer. Depending on the starting materials and the length of time it is allowed to stand before it is applied to the soil, compost may or may not be a good source of the trace elements necessary for plant growth. The same is true for the macro?nutrients, which are leached from compost if it is allowed to stand unsheltered in the rain.

So remember,

"Spring has sprung
Fall has fell
Leaves are here
So use them in the compost pile!"

Even though it doesn't rhyme, it makes good sense.

For more information about composting, see:

http://aggie-?horticulture.tamu.edu/extension/gardcom.html

http://aggie-horticulture.tamu.edu/earthknd/compost/compost.html

http://aggie-horticulture.tamu.edu/sustainable/slidesets/kidscompost/cover.html