COMPOST, DON'T BURN!
By Dr. Leonard Perry,
Extension Professor, University of Vermont
You may like the smell of burning leaves, but did you know you were sending
an excellent soil conditioner up in smoke? Instead of burning leaves or stuffing
them in garbage bags for the trash haulers to take away, compost them.
Compost Improves Soil
Compost improves garden soil by increasing its organic matter. This, in turn,
improves soil drainage. Organic matter is especially beneficial in heavy clay or
light, sandy soils. Organic matter reduces soil crusting and helps soil hold
water and nutrients.
The compost also supplies a small amount of nutrients. Compost can be used
as a mulch around plants, too. Mulch helps conserve moisture as well as
reduces frost heaving.
How Leaves Become Compost
Microorganisms are what decompose materials to make compost. To do their
work they need carbon sources for food, and nitrogen for proteins. They are
most effective when the ratio of carbon to nitrogen is an average of 30 to one, by
weight. You don’t need to weigh what you add to the compost pile, just be
aware of approximate amounts you’re adding.
In general, course woody material (sawdust, leaves) is high in carbon. Moist,
dense material (manure, grass clippings) is high in nitrogen. Too much carbon
materials and the compost pile will decompose slowly. Too much nitrogen and
you may smell ammonia gas.
How to Compost Leaves
To compost leaves, alternate leaves with layers of soil or manure. Make layers
of leaves six to 12 inches thick, layers of soil or manure about one inch thick. To
hasten decomposition, shred leaves first with a rotary lawn mower or shredder.
For each bushel of organic material, add one cup of complete fertilizer such as
10-10-10 and two-thirds cup ground limestone. Moisten each layer. Finish the
compost pile by slightly rounding the top to help the pile hold water. Cover
with an inch of soil.
Next, cover the compost pile with plastic. Hold the sides in place with wire,
concrete blocks, or boards. Turn the pile every few weeks throughout the fall,
adding moisture during prolonged dry periods. Both will help speed
decomposition and make the final product more uniform. Compost piles are
simple to do, but it does take time for the process to work. If you start a
compost pile this fall, don't expect to use it in the spring. However, it should be
ready to spread next fall.
Keep in mind that you are not limited to leaves for composting. You can use
any plant material that's not diseased, doesn't contain mature weed seeds, and
hasn't been treated with pesticides. In addition, non-meat kitchen scraps can be
Plant materials and products that are easy to compost, and generally
decompose most rapidly, include egg shells, coffee grounds, pine needles,
fruit peels and rinds, paper, sawdust, straw (not hay, as hay often contains
weed seeds), vegetables, tea bags, wood ash, and wood shavings. Materials
that are slow to decompose and may take two years to break down include
coarse wood chips, branches, corncobs and corn stalks, and nut shells. Breaking
these materials into smaller pieces, and adding high nitrogen materials will
speed up their composting.