Gardening Tips: Nov. 18, 2009

It is nice to be able to produce wonderful compost in your own backyard at little to no cost. Fall is the ideal time to create a compost pile but keep in mind that the compost may not be ready to use until next fall. Those of you who started a compost pile last fall may be applying it to your garden beds right now. Here is how you can get started this week!
Start with a layer of fallen leaves that you rake from the lawn. Maple leaves decompose pretty quickly and a one-foot thick layer is fine for maple and most other species of tree leaves, but if you are raking oak leaves, use only a three- to six-inch layer since they decompose very slowly. Shredded leaves or shredded vegetable matter of any sort will decompose much quicker than plant material that is intact. Put a layer of garden refuse on top of the leaves such as spent tomato plants, bean plants, zucchini vines, and all the dead or dying annuals from your flower garden. Large, tough or woody plant materials do not compost well so avoid corn stalks, Brussel sprouts stems, ears of corn and woody twigs thicker than your pinky unless you can shred them first. A thin layer of fresh, green grass clippings on top of this will supply nitrogen but make it a thin layer since grass also tends to mat up.
Throw a few handfuls of soil on top of each layer to supply the microbes that will actually break the material down. No need for a compost starter or any other addition such as lime or fertilizer. There are literally millions of microbes in even a single tablespoon of soil and for some reason all compost ends up with a neutral pH, even if pine neeedles are used. Remember to think of lasagna as you repeat this layering process over and over until the pile is up to five- feet high. You can compost vegetable kitchen or fruit scraps or even cooked vegetables but no meat, pasta or bread.
Wet the pile down if rain is scarce (Ha!) and let nature take its course. If outdoor temperatures remain above 50 degrees for a couple of weeks the pile should begin to heat up and may produce steam. Ideally the pile will attain a temperature of about 160 degrees, which is hot to enough to pasteurize it but not so hot as to sterilize it. After it cools down, turn the pile with a pitchfork to aerate it. Compost piles that fail to heat up can usually be jump started by turning which supplies oxygen. Compost is considered “finished” when you cannot distinguish the original materials that went into it. Since different materials decompose at different rates, it is usually necessary to sift it through some sort of screen such as chicken wire. Stuff that has not completely broken down can be returned to the pile for the next cycle.