Oregon State University Extension Service


Grass clippings too toxic to compost?

Once or twice a summer I treat my lawn with weed & feed and spray on weed killer for lawns. Is it safe to use compost made from the lawn clippings? How long should I reasonably wait to use clippings for compost, and is it safe to use the compost in my veggie garden the following summer?

Mowing recommendations are to set the blade of the mower so that you remove one-third of the stand of grass with each mowing. If you follow that recommendation, you would dispose of the clippings resulting from the first three mowings following a weed-and-feed application. From the fourth mowing on, the clippings would be fine to include in your compost and to apply to a vegetable garden.


Source URL: https://extension.oregonstate.edu/ask-extension/featured/grass-clippings-too-toxic-compost