Hi all, Lane County Extension Service Master Gardener John Fischer here with KLCC's Good Gardening.
Perhaps you remember those old radio dramas - probably not - they were from my parents day. Nonetheless, today's episode is "The Case of the Missing Compost" (organ music) John had been putting kitchen scraps and garden waste into his composter for 2 years - and it was only half full - and disappearing fast" Were all those corn stalks, weeds, tomato vines, apple pressing scraps and the like vanishing into thin air.
Jan Baptist van Helmont had the opposite question around 1620. After growing a tree in a tub he got 169 pounds of tree and his 200 pounds of soil lost only two ounces . Was the wood being created out of thin air.
One fact answers both questions. The tree was made of mostly water and CO2. The plant waste in the composter is mostly the same. When the worms, soldier flies, and micro organisms chew through what you compost, they get energy, and release water and CO2. So you don't really get a lot of compost.
A good hot compost pile only breaks down about half of what you threw in completely. The rest degrades slowly once it is in your garden, and provides valuable organic matter to the soil. But hot compost is very hard for the home gardener to get. The pile needs to be three by three by three. No bin is that big, and open piles can attract animal pests.
Just letting garden waste and kitchen scraps decompose in a bin will get rid of the material without hauling it across town, and provide you with some organic matter for your soil.
Keeping organic matter in your soil requires that you constantly add it. There are rare cases where plant material does not break down. Peat bogs and coal beds both contain most of the plants that formed them. But as you clean up the yard and garden this fall, and fill your bin or pile with spent vines, grass clippings, rotten tomatoes and the like, don't be surprised that all your work gives you next to nothing next spring.
I'm John Fischer with Good Gardening.
