Organic matter improves soil as a growing medium for plants. It helps release nitrogen, minerals, and other nutrients for plant use when it decays. A mulch of partially rotted straw, compost, or undecomposed crop residue on the soil helps keep the soil surface from crusting, retards water loss from the soil, and keeps weeds from growing.Practically any plant material can be composted for use in the garden. Leaves, old sod, lawn clippings, straw, and plant refuse from the garden or kitchen can be used. Often, leaves can be obtained from neighbors who do not use them or from street sweepings.
The purpose of composting plant refuse or debris is to decay it so that it can be easily worked into the soil and will not be unsightly when used in the garden. Composting material should be kept moist and supplied with commercial fertilizer, particularly nitrogen, to make it decay faster and more thoroughly.
The usual practice in building a compost pile is to accumulate the organic material in some out-of-the-way place in the garden. It can be built on open ground or in a bin made of cinder blocks, rough boards, or wire fence. The sides of the bin should not be airtight or watertight. A convenient time to make a compost pile is in the fall when leaves are plentiful.
In building the compost pile, spread out a layer of plant refuse about 6 inches deep and add one-half pound or one cupful of 10-10-10, 10-20-10, or 10-6-4 fertilizer to each 10 square feet of surface. Then add 1 inch of soil and enough water to moisten but not soak it. This process is repeated until the pile is 4 to 5 feet high. Make the top of the pile concave to catch rainwater.
If alkaline compost is wanted, ground limestone can be spread in the pile at the same rate as the fertilizer.
The compost pile will not decay rapidly until the weather warms up in spring and summer. In midsummer, decay can be hastened by forking over the pile so moisture can get to parts that have remained dry. The compost should be ready for use by the end of the first summer.
For a continuing supply of compost, a new pile should be built every year. Compost can be used as a mulch, or worked into flower beds and the vegetable garden.
When properly prepared and thoroughly decayed, compost is not likely to harbor diseases or insects. If the compost is used in soil where an attempt is made to control plant diseases, or if it is mixed with soil used for raising seedlings, the soil should be disinfected with chemicals recommended by your local Extension agent or State agricultural college.