Protect compost from rats - Ask Extension
Hi , I stopped composting during the pandemic due to too many rats in the neighborhood. Now I want to get back to composting but fear the rat invasion...
Knowledgebase
Protect compost from rats #927703
Asked April 07, 2026, 2:04 AM EDT
Hi , I stopped composting during the pandemic due to too many rats in the neighborhood. Now I want to get back to composting but fear the rat invasion to start all over again. How to keep rats out of my compost bin made of some sort of plastic, it has slits in the sides for air circulation, and a solid lid. Thanks!
Lane County Oregon
Expert Response
I'm the wildlife ecologist and rats are not wildlife, however your question was routed to me, so I'll do my best.
Building a compost that runs "hot" is the first and most important practice, along with never-ever putting meat, dairy, bread, or oil in the heap. A compost that is "cold" enough for there to still be edible (to rats) material is how compost becomes a rat-magnet. So, start with building a hot pile, then install un-chewable exclusion (i.e., 1/2 inch welded hardware cloth).
It sounds as though your bin is not a tumbler - Tumblers help stir materials and thus help heat things up. So with a fixed bin, you'll have to commit to doing regular stirring to build and retain the heat of the composting process. Also check out this resource: https://extension.oregonstate.edu/catalog/em-9475-do-rot-thing-choosing-using-composting-system
Trying to rely on exclusion alone will not yield success, but exclusion in combination with careful construction and movement of the mix in your bin will help alot.
Your county Master Gardeners likely also have some excellent resources on best-practices for composting.
Non-native, invasive rats are unfortunately very well-established in our human cities and towns, but they're always looking for easy meals. Controlling access to and composition of your compost is one step in reducing rat use of your yard, but doing other things such as making sure there's no access to bird feeders or spillage, or free meals from pet or small livestock food, or even garbage is also very important.
Building a compost that runs "hot" is the first and most important practice, along with never-ever putting meat, dairy, bread, or oil in the heap. A compost that is "cold" enough for there to still be edible (to rats) material is how compost becomes a rat-magnet. So, start with building a hot pile, then install un-chewable exclusion (i.e., 1/2 inch welded hardware cloth).
It sounds as though your bin is not a tumbler - Tumblers help stir materials and thus help heat things up. So with a fixed bin, you'll have to commit to doing regular stirring to build and retain the heat of the composting process. Also check out this resource: https://extension.oregonstate.edu/catalog/em-9475-do-rot-thing-choosing-using-composting-system
Trying to rely on exclusion alone will not yield success, but exclusion in combination with careful construction and movement of the mix in your bin will help alot.
Your county Master Gardeners likely also have some excellent resources on best-practices for composting.
Non-native, invasive rats are unfortunately very well-established in our human cities and towns, but they're always looking for easy meals. Controlling access to and composition of your compost is one step in reducing rat use of your yard, but doing other things such as making sure there's no access to bird feeders or spillage, or free meals from pet or small livestock food, or even garbage is also very important.
