My parents have a compost pile in their backyard. It’s something we’ve always had, and it’s something we constantly maintain. Even though I grew up with a decent understanding of compost, there were still things about composting that I didn’t know. Composting is an important tool for our planet. Here are some basic questions and answers about compost and composting.
What is compost?
Compost is decayed organic matter, according to Green Matters. Compost starts out as green and brown material. Over time, the material, when mixed with water, is broken down into a nutrient-rich fertalizer that looks and feels like soil. Compost piles contain microbes, which break down the materials.
What are green and brown materials, and are they important in a compost pile?
Green materials are nitrogen-rich matter, that usually contain water, like fruit and veggie scraps. Brown materials are carbon-heavy and tend to be dry, like plant trimmings and sawdust. In a compost pile, it’s important to keep an even mix of green and brown materials. Nitrogen helps break down materials, but too much nitrogen causes unwanted odors. Carbon provides energy for the microbes that break down the material, but too much carbon can cause the process to slow down.
What can I compost, and what can’t I compost?
These items can be composted:
- Fruit and vegetable scrap
- Items made from grains, like bread, cereal, and pasta
- Coffee grounds and coffee filters
- Tea leaves
- Herbs and spices
- Nuts
- Egg shells
- Non-diseased cut flowers and plant trimmings
- Shredded newspaper
- Cardboard
- Paper
- Yard trimmings
- Grass clippings
- Houseplants (non-diseased)
- Hay and straw
- Leaves
- Sawdust
- Wood chips
- Cotton and wool rags
- Dryer and vacuum cleaner lint
- Hair and fur
- Fireplace ashes
These items can’t be composted:
- Animal products, like meat, dairy, fish, and animal fat
- Anything oily or greasy
- Pet waste, which could introduce diseases to the compost pile that makes it unusable
- Black walnut tree leaves or twigs
- Coal or charcoal ash
- Diseased or insect-ridden plants
- Yard trimmings treated with chemical pesticides
What are the benefits to composting?
Compost is a valuable tool for farmers and gardeners because it boosts water retention in the soil, which in turn reduces the need for constant watering, and facilitates a bigger crop yeild. Composting also reduces methane emissions from landfills, reduces the need for chemical fertilizers, and aids in carbon sequestration (traps and contains carbon, keeping excess carbon out of our atmosphere).
How do I start a compost pile?
Starting a compost pile is easy, but it depends on the location. If you plan on having an outdoor pile, you simply need a large tub or a fenced-in area on the ground. To start, simply mix your green and brown material with a little water, then turn the pile with a shovel every other week. Turning the pile allows oxygen to mix in.
Starting an indoor compost pile is a little trickier, because you don’t have as much space and it is messy. Most garden centers will have indoor compost bins, which can be placed on your kitchen counter or in your fridge. Once the container is full, you can drop off the compost at a local farmers market or community garden, if it’s available.
Another form of indoor composting is vermicomposting, which uses worms to break down the compost pile. To start a basic vermicompost pile, fill a bin with organic bedding (shredded newspaper or leaves), mix in a little soil, add the worms, then feed them normal compost materials. To reduce odors, keep a lid on the bin and store in the fridge.
My indoor compost bin, which I mostly use for dumping old coffee grounds and avocado pits. (OXO Good Grips Easy Clean Compost Bin, White, https://www.amazon.com/OXO-Grips-Clean-Compost-White/dp/B003ZFW0YQ/ref=s… $19.94)
How long does it take material in a compost pile to change?
It takes months for a pile to completely change, but it should be noticable after a few weeks. If it’s been several weeks and nothings has happened, you might need to evaluate which type of material you mostly throw in the pile, then adjust the other material. Another issue might be the amount of moisture in the pile. If it’s really dry, the microbes won’t break down material, so keeping the pile moist is important.
Where else can I find information on composting?
The EPA has a page that’s a great starting point for researching compost (https://www.epa.gov/recycle/composting-home). Green Matters also has a nice page that touches on the basics of composting, and a few other areas I didn’t cover, like composting toilets (https://www.greenmatters.com/food/2018/12/07/ZboPlt/what-is-composting).
If you want to find out more about vermicomposting, the EPA has directions for starting a basic vermicompost pile (https://www.epa.gov/recycle/how-create-and-maintain-indoor-worm-composti…).