Q: Can I compost my cat litter?
— B.F., Cuyahoga Falls
A: Composting pet waste is possible, but doing so safely at home is complicated and time-consuming, said Fred Michel, an associate professor of biosystems engineering and a composting specialist at Ohio State University’s Ohio Agricultural Research and Development Center.
Cat and dog waste contain pathogens that can harm humans — in dogs, large roundworms; in cats, the organism that causes toxoplasmosis, a disease linked to birth defects. In a typical home compost pile, it can take up to a year of active decomposition to kill those pathogens, Michel said. And that doesn’t include winter, when composition slows or even stops.
To make sure those pathogens are eliminated, you can’t add any fresh animal waste to the compost pile during that decomposition time, Michel said. That means you’d need to maintain multiple piles, one that you add to regularly and another one or more piles that are maturing.
You also need to be careful about the kind of cat litter you choose. Most litters are made of clay, sand or crystalline-based materials, which can’t be used in compost piles, he said. Only litters made from biodegradable sources can be composted, such as sawdust, pine or recycled paper.
Michel said another complication is that animal waste by itself will compost poorly, with a bad odor and a poor structure. He said animal waste should make up no more than 10 percent of the compost pile, with the rest comprising other organic matter such as leaves, food waste, brush and finished compost. Many homeowners wouldn’t have enough of the other organic materials to mix with the animal waste, he said.
Even with all those precautions, he suggested using compost containing pet waste only on ornamental plants or grass, not on food crops.
Have a question about home maintenance, decorating or gardening? Akron Beacon Journal home writer Mary Beth Breckenridge will find answers for the queries that are chosen to appear in the paper. To submit a question, call her at 330-996-3756, or send email to email@example.com. Be sure to include your full name, your town and your phone number or email address.