Composting Workshop 4-26-11

To request a free compost bin from the City of Hyattsville, contact the Hyattsville DPW at 301-985-5032

1) Compost piles are living things and need FOOD, AIR, and WATER in certain amounts.

a) FOOD: Food is composed of green (nitrogen) and brown (carbon) materials. Common sources in households are spring and summer grass clippings and leaves picked up in the fall using a bagging lawnmower. Kitchen waste is usually green. Households should stay away from adding meat, dairy, and pet waste. A good mix is 3 shovels of brown for every one shovel of green. If the pile smells bad, there is too much green. If it isn't hot, there isn't enough green, air, or water. When you are adding material, make sure the green and brown is mixed. Alternating layers of green and brown aren't very effective.

b) AIR: Air is needed by the bacteria that use an aerobic cycle. (Yes, I know this is circular.) The aerobic cycle is fast and isn't smelly. The anaerobic cycle is slower and is smelly. The traditional way to get air into the pile is to turn it. Lazy people rejoice: there is a better way!

Turning the pile releases a lot of the nitrogen into the atmosphere that can be kept in the compost. The oxygen introduced by turning is consumed by the pile in 30 minutes. Instead, lay a set of perforated 4" white PVC pipes into the bottom of your pile. The heat of the pile will pull air from these pipes using a chimney effect.

If you are creating a new pile, lay the pipes on the ground with the holes facing upward. Cover the pipes with wood chips or straw, and then start your compost pile on top of the wood chip layer.

c) WATER: how much is enough, how much is too much? Use the squeeze test. Pick up a handful of your compost pile and squeeze it. Does water drip out?--it is too wet. Does it fall apart easily?--it is too dry. Does it stay together?--just right!

2) More tips:

a) TEMPERATURE: How hot is hot enough? 130 degrees F for at least three days is good for killing bad things. If you stick your hand in the middle of the pile and it is uncomfortably hot, that is a good sign. You can also buy a compost pile thermometer for $30 from Purple Mountain Organics, a local supplier.

b) IS IT DONE YET? Over time you can develop a feel for what is finished compost. You can test a batch by putting it in a garbage bag, add a little water, seal it, and leave it outside a few days. Open it up. Stinky?--not done yet.

c) STINK MANAGEMENT: Make sure there is enough carbon and air. If necessary, you can add a "carbon cap" of wood chips which will do a good job of absorbing a lot of the nitrogen-based odors.

d) WOOD CHIP SOURCE: Asplundh--the contractor with the orange trucks that go around trimming trees away from power lines. If you see a truck, stop and tell them to dump a load behind your house.

e) PILE MANAGEMENT: Piles need time and solitude to work. If possible, have two piles--one that is finishing off and not taking new material and another that is still being built.

e) WHERE ARE THESE PEOPLE? The presentation was given by Christian Melendez of Eco City Farms. They are located near Community Forklift in Edmonston at 4913 Crittenden. You can meet them at the Riverdale Park Farmer's Market. Kudos to Ms. Morgan-Hubbard of Hyattsville for getting this organization started!