Creating a Yard Waste Compost Bin
Gather the Materials Needed
A yard waste compost bin can be square or round and stationary or movable. It can be made of plastic or built from plywood and two-by-fours with wire mesh. A holding unit's size can vary depending on the amount of yard waste one gathers and how fast a person wants compost to be produced. Piles smaller than three feet cubed (27 cubic feet) may have trouble retaining the heat generated from the microbial activity and piles larger than five feet cubed (125 cubic feet) do not allow enough air to reach the microbes at the center.
Good compost components will give yard waste a carbon:nitrogen ratio of about 30:1. For example, a good combination is grass clippings (nitrogen) and leaves (carbon). Carbon is an energy source for the decomposers and nitrogen provides the protein for their bodies. Composting yard waste without this balance and proper moisture and aeration may produce bad odors and inhibit material breakdown. Shredding or chopping materials will allow for faster breakdown and room for more materials.
Materials To Use
- Grass clippings
- Sawdust, straw, hay
- Remains from plants
Materials Not to Use
- Weeds with seeds
- Unchopped branches
- Food waste
- Diseased plants
- Pet waste
Where to Set Up A Yard Waste Compost Bin
Choose a location for the yard waste bin that is protected from direct sunlight and extreme cold, and that has good air circulation. This location may be on the side of a house, on a patio or deck or in a garden. Keep in mind that liquid may come out of the bin's drainage holes.
Yard Waste Materials Timeline
Depending on the types of materials used and the amount of time spent taking care of the bin, compost can be ready to harvest anytime from two month to two years. Patience is a must.
Mixing Yard Waste
About once a week use a pitchfork, shovel, or other tool to turn the material in the yard waste bin. Try to alternate the type of materials placed in the bin each occasion, which allows for a proper carbon to nitrogen ratio. When turning over the yard waste, check the material in the bin to make sure it is moist. Add water with a spray bottle or watering can if it is too dry. If it is too moist, check the drainage holes on the bottom of the bin. Some waste may decompose faster than others. This is mostly due to water content and size.
Harvest Compost and Prepare Fresh Material
After a few months, the volume of the bin contents should visually decrease. At this point it will look more like compost than yard waste material. When this happens the compost may be harvested to allow room for new materials. Remove the compost and use it in the garden as a soil additive, with house plants as potting soil, as mulch around trees and shrubs, or sprinkle a thin layer of compost on the lawn.
Answers to Common Questions
What are the critters in the yard waste compost bin? Will they affect the breakdown of the yard waste?
Once a yard waste bin has been going for a while, creatures like centipedes, millipedes, earthworms or beetles might be spotted living in it. This is normal and these creatures will not hurt the yard waste. In fact, they help the composting process. However, be careful with the type of lawn and garden products, such as fertilizers, that may make their way into the bin via grass or flowers. These products can kill organisms and slow decomposition. Instead of store bought fertilizer, place finished compost in a gunny sack, immerse the sack in rainwater for three days and then pour the nutrient-rich liquid contents over plants and soil.
The bin smells awful. What to do?
Unpleasant odors in a yard waste compost bin may result from too much yard waste, too much moisture or not enough aeration. Odors can be controlled in the following ways: remove excess or inappropriate wastes, make sure drainage holes are not blocked and/or add new materials.
Is that mold growing in the yard waste compost bin?
Patches of fungi and mold are a natural part of the composting process. Both help to breakdown yard waste. During the decomposition process, the fungi and mold will be consumed by the above mentioned organisms.
Why is the composting pile cold or only warm in the center?
This means there is not enough material or that the outside layer is exposed to dryness. Add nitrogen rich material.
The center of the pile is dry?
This means there is not enough water. Add moisture and then turn the pile.
What happens to the yard waste compost bin in the winter?
When it gets cold, yard waste decomposition will slow down. It will most likely be necessary to cut back on the amount of yard waste added to the bin between November and February.
How to use the compost?
Compost is extremely nutrient rich and helps soil hold moisture. As such, it should be used sparingly. Uses include sprinkling some in the bottom of seed rows or transplant holes, or using it as a top dressing for house plants. It may also be mixed with peat or other materials to make potting soil. When using compost for house plants, consider "cooking" the compost between sheets of black plastic in the sun for a few hours. This will get rid of most of the critters found in the compost.
For questions or more information, contact the Natural Lawn and Garden Hotline at 206-633-0224. Citizens may call and request the free guide Composting at Home or refer to the Harmonious Technologies book entitled Backyard Composting: Your Complete Guide to Recycling Yard Clippings.
Email the Solid Waste Coordinator