Ask the Gardener: Which Kind of Mulch Repels Termites?

Ask the gardener is a column in which local readers send in questions about your garden, lawn, trees and more. 

This week's question: I'd like to put down mulch in the garden in front of my house, but I'm concerned about termites. Is there a certain type of mulch that termites don't like?

Scott Killpack, program director of the St. Charles County Extension Center, answered the question:

"You could even have rock mulch and no wood mulch at all and the potential for termites won't be any different. It is the condition of moisture level and so forth that is created by the use of mulch that increases the likelihood or the potential of termite issues. The mulch by itself is kind of a moot point.

Certainly with any kind of mulch, if you can pull it away a few inches from the foundation that is always helpful because then you have a zone that’s going to be a little bit drier. You never want to have mulch piled up against the siding or the façade of your home. If it’s up against the concrete footing that’s probably OK.

But again, the real crux of this questions is not whether it’s a certain type of wood mulch but mulches in general, any kind of mulch that’s going to increase the moisture levels. Termites by their behavior must have very high humid environment.

(People use mulch to) conserve moisture, they also use it to help to keep weeds down. The only thing I would advise is just keep it several inches away.

So is one type of mulch (such as cedar mulch) less hospitable to bugs? That’s a non-issue. There is really no independent verification that one mulch is less risky than any other it has every thing to do with how the mulch is managed.

Have another question about mulch? Reach out to the St. Charles County Extension Office at 636-970-3000.

Have question about gardening? Leave it in the comments and we'll try to track down the answer.