Page 12 - Sonoma County 2016 Gardeners Resource GUide.indd

Make your own Compost
By Will Bakx
Now that Sonoma County is exporting 100,000 tons of organics per year, the
landscapers, farmers and backyard gardeners find themselves faced with a shortage of local compost. Making your own compost may be your best bet to assure that you can still feed your garden. Here are some simple guidelines to make a good, living compost pile.
Just like us, the compost needs air, water, food and time to mature. When you get all of these parameters together in the right amount you will get some great compost.
Composting is the managed decomposition of organic matter.
All organic matter will rot, break down eventually, but in composting we manage the process to get the desired end-product. That means we have to pay attention, monitor and take care of the compost pile.
If you like the looks of a contained compost pile, some sort of a compost bin would be required. But, it is not necessary, a free-standing pile works well.
You just have to work a bit harder to get those vertical sides as steep as possible. A simple, cost-effective bin can be made of fencing wire.
You will need a minimum pile of 3 feet by 3 feet by 3 feet. A 15 foot section of fencing wire will give you a nice sized pile. The advantage of fencing is that you can make the diameter smaller as you rebuild the pile to maintain a pile height of 3 feet or higher. You could also put together 4 wooden pallets. It is recommended to build the pile at least 5 feet tall and just as wide, since it will shrink to about half its original size.
In composting we are basically farming microorganisms. The microorganisms are already omnipresent, so no introduction is needed.
They just need the right balance of food. To simplify the right diet we are
using browns (carbon) and greens (nitrogen). Woody material, dried leaves and weeds, straw are brown materials and fresh weeds, lawn clippings and vegetative food scraps (meat, fish and dairy are not recommended) are greens.
Horse manure is a brown, but chicken manure is a green, no rule is fool proof. If you use 5 parts of brown to 1 part of green you should get a pretty good mix. Or you can build a blend with a carbon to nitrogen ration of 30:1. This calculator is useful for that purpose: http://compostingtechnology. com/resources/compost-calculator/
All life needs water and so do the microorganisms in the
compost pile. The ideal moisture content is between 40 and 60 percent. The material should feel like a wet sponge and hold together when squeezed. If it does not hold together it is too dry, if water comes out when squeezed it is too wet and the pile will lack oxygen, becomes stinky and slow down in decomposition.
The compost pile also needs oxygen. When the particles are too fine it is hard for the oxygen to enter the pile and the microbes can not function well, at least the aerobic ones that we want to grow. Having a particle size of 1-2 inches is ideal. When the organic matter is too coarse the pile will not hold heat. We want the pile to heat up.
If the compost pile was build with these guidelines in mind, the pile should heat up to over 131°F within
a few days. A compost thermometer is highly recommended if you are serious about making your own compost. The temperature will tell you how well the compost is doing. When the temperature rises over 170°F the pile should be turned, if not a fire may result.
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A well built compost pile will give you finished compost any time between 3-6 months, depending on how often you turn it. There is no need to turn more than twice per week, but turning every 2-4 weeks should be fine for a backyard pile. The more frequently turned pile is finished faster, but it takes more labor. When you rub the compost between your fingers and you get a black stain, that is a pretty good indication that your compost is ready. Keep notes so that you can go back and see what did or did not work for you.
Most of all, have fun making your own compost knowing that your garden and the environment will love you for it.
The compost should be turned
several times to make sure that all
material has been exposed to the temperature of 131°F or greater to assure that any diseases or weed seeds will be destroyed.
When the pile is turned make sure that the pile is still moist enough and that it has the minimum pile dimensions of 3’ x 3’ x 3’. It is not recommended to keep adding fresh material to the pile, because each time you do the process starts all over. That is why you start with a larger pile