Composting
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Why composting is important:
Composting allows you to turn trash into treasure by creating a valuable soil amendmentSoil Amendment A material or substance added to soil to improve its fertility or structure.. Compost is created by microbes that break down organic materials through decompositionDecomposition The process of organic matter breaking down into smaller parts.. This helps reduce how much organic debris we send to landfills while also recycling nutrients within the watershed.
Composting is a great way to make use of food scraps, yard debris, crop residue, and manure by converting waste into a nutrient-rich substance that boosts soil health. Compost can be used as natural fertilizer for plants in your home, garden, or farm.
How does compost help the soil?
Healthy soil has about 5% organic matter. If soil is lacking organic matter, compost can be added to boost overall health and productivity. Compost improves soil structure by creating pore spaces for air and water. This helps prevent erosion and creates habitat for organisms. Soil with higher organic matter content can hold more water and has better infiltration, meaning that water can seep into the root zone where plants need it most.
Composting tips:
How can you get started with composting?
There are many different compost systems available for home use. Whether you only have space for a countertop unit or a yard that can handle a larger pile, there is a composting method that will work for you.
Regardless of which method you use, the key to composting is to mix “browns” and “greens.” Brown materials, like dry leaves or cardboard, are high in carbon and provide food for the soil microbes. Green materials, like grass clippings and food scraps, are rich in nitrogen.
Compost piles should be kept moist (aim for the consistency of a wrung-out sponge) and should be turned every few days to introduce more oxygen, which is necessary for the decomposition process. Get more composting tips from Metro and check out these methods below:
- Worm compost bin
A worm compost bin is a great way to compost if you have limited space. This compost method can take care of food scraps and paper. It will only produce a small amount of compost, but it’s great for adding to indoor plants and patio gardens. Composting with worms (called vermicultureVermiculture Composting with worms.) is a process that uses red worms in a container to process compostable material into nutrient-rich compost.
- Open air or bin composting
Open air or bin composting systems are the methods most folks have in mind when they think of the compost pile. They require relatively low effort to maintain, but care needs to be taken to balance the green and brown materials in the pile. These composters can handle food scraps and a variety of yard debris. Usually the finished compost filters to the bottom and can be removed a few times a year to be used in your garden.
View "Bin Compost System" (PDF) - Hot compost
A hot compost system requires a bit more space and attention, but it gets the job done a lot faster! A hot compost pile accelerates the decomposition process, meaning you’ll be able to use your homemade compost after several weeks. This is a good option for people who have a large quantity of organic materials to process.
View "Hot Compost System" (PDF)
- Are you having trouble with your composting system?
Check out Metro’s suggestions for troubleshooting compost issues.
Composting at your home:
Compost can be used as a potting mixture for your house plants and container gardens, or as a fertilizer for your yard or farm. It can also be used as a mulch and can come in handy if you’re using sheet mulching to remove unwanted lawn.
Composting on your farm:
Crop residue and waste from livestock make for great compost! Establishing a process for composting on your farm will help you manage the volume of organic waste while also creating a valuable soil amendment. Before starting large-scale composting on your property, consider what your site can handle. Compost facilities should be placed on a gentle slope, far away from any surface water, wells, and septic systems.
Common methods of on-farm composting include turned windrows and aerated static piles. If you have livestock, consider composting manure to reduce the volume of material and create a soil amendment or bedding.
If you are composting over 100 tons of organic material per year, you need to meet specific design standards or acquire permits from the Oregon Department of Environmental Quality’s Composting Program.