Grubs in grass and garden


Skunks and/or raccoons are digging up lawn or tossing sod to get to grubs which I know I have. I use nematodes to control grubs. Is it too early to apply nematodes given its barely mid August. I know it is ideal to wait until late August at least before applying but I don’t want to have to deal with fixing many more holes. Thank you


Thank you for contacting Toronto Masters Gardeners about the usage of nematodes on your grass and garden. Although we share our plant spaces with other natural inhabitants, it can be challenging to repair their digging in lawns, and consumption of plants. You’ve chosen a responsible way of dealing with this problem that won’t affect pollinators or other beneficial creatures. The use of nematodes to combat white grubs is effective in spring or late August when the soil temperature is above 15 degrees C. Given it is almost mid-August, waiting for another week or two would be ideal.

De-thatching your lawn before application will help the liquid solution penetrate grass roots. Also, over-seeding the lawn will strengthen the lawn/soil composition and help combat future grubs. Depending on the degree of rainfall in your area, it’s better to wait until overly soggy ground dries out a bit. Although after application, the lawn should be kept relatively moist for 2 weeks. In May next year, you could re-apply the solution, and the nematodes should contact the grubs within 2 days and be completely effective within 14 days.

Toronto Master Gardeners receive many questions about nematodes and the links below describe comprehensive info on their usage.

Nematodes – when to use

Grubs and Japanese beetles in lawn

Grubs in lawn

Hopefully the repair of your lawn will lessen in time and it will become a lush, thick green carpet. Perhaps with some easy-care, native ground cover in some spaces too! See link to Guelph ground cover suggestions below.

Ground cover alternatives to grass