Can I put insect-ridden plants in my compost bin?

NO ✋🏼

You can't put insect-ridden plants into your composting bin!

Can You Put Insect-Ridden Plants in a Compost Bin? A Detailed Guide

Putting insect-ridden plants in a compost bin is not recommended. Read this comprehensive guide to learn why insect-ridden plants should be avoided and what alternatives exist for proper composting.

Insect-ridden plants refer to plants that are infested with insects, pests, diseases or other bugs. Examples include plants with aphids, squash bugs, powdery mildew, or other infestations. Many homeowners wish to compost all their yard waste but wonder if diseased plant materials can go in the compost or if they need to be handled differently.

We recommend avoiding putting insect-ridden plants into backyard compost bins. There are a few key reasons why:

Insects and Diseases Can Spread

Compost piles typically do not get hot enough or compost long enough to kill off most plant diseases, fungi, bacteria, viruses, and insects. Tossing diseased plants into compost risks spreading pathogens back into your garden later on. Fungal spores, cheatgrass seeds, root maggots and other pests may survive composting.

Can Attract More Pests

Rotting, pest-ridden plants can attract further pest invasions to your compost from flies, rats, raccoons or skunks. Meat-eating scavengers go where the food is, and a pile of moldy, bug-infested plant waste is an open buffet! Keep diseased waste enclosed in trash bags to discourage additional scavengers.

Produces Bad Odors

Insect or disease damaged plants contain more anaerobic bacteria and smell worse as they decompose. This increases complaints from neighbors and decreases your enjoyment of maintaining a backyard compost pile.

Lowers Compost Quality

The benefits of compost come from rich, healthy soil microbes that develop during the breakdown process. Tossing diseased plant materials into compost disrupts the microbial community and can lower the quality and benefits of your finished compost.

Frequently Asked Questions About Insect-Ridden Plants in Compost Bins

Can I put plants infested with aphids in my compost?

No, it's best not to compost aphid-infested plants. The insects and eggs can survive standard composting and spread back to your garden plants later.

What about plants with powdery mildew or other fungus - can I toss them in my compost tumbler?

No. Like other plant pathogens, fungal spores and mildew may survive backyard composting. Discard diseased plants in household trash bags to avoid spreading fungus back into your garden soil.

Can I put tomato hornworm infested tomato plants in my pile?

It's risky to compost any insect-ridden plants. Tomato hornworms can survive composting and spread back to future tomato crops if added. Instead, throw the infested plants away in bags.

What if I hot compost the diseased plants - would high temperatures eliminate the bugs and diseases?

Maybe, but maintaining sufficiently high temperatures over long enough time can prove difficult in home compost piles. Safest bet is to leave out insect-ridden plants entirely to avoid recontaminating gardens later.

Recommended Alternatives for Insect-Infested Yard Waste

We recommend the following alternatives for handling yard waste with heavy insect, disease or pest damage:

Trash removal: Place heavily infested plant materials into trash bags for waste pickup. This fully contains pathogens and pests so they cannot spread.
Solarization: Solar heating weed seeds, pests and diseases in sheet mulches spread atop soil can provide control when done properly over weeks.
Burning: Where allowed by local ordinances, burning waste plant materials can destroy pests and diseases prior to burying ashes onsite. Use extreme caution when burning plant waste.
Hot composting: Use multiple turnover batches and monitor internal temperatures to maintain 140-150°F+ for pathogen control. This kills most bugs and diseases.
Trench composting: Bury diseased waste deeply under fresh soil to decompose underground, which filters pathogens prior to releasing nutrients slowly.

Proper hot composting, batching and curing times do allow the safe breakdown of some diseased plants. However this requires careful active management not practical for most homeowners. Erring on the side of caution by excluding insect-infested plant materials from backyard compost bins is wise to avoid creating pest reservoirs reinfecting future gardens.

Hopefully this guide has helped explain why composting insect-ridden yard waste is risky and best avoided. Please leave any other composting questions below in the comments!