Crab grass preventer

Asked April 4, 2017, 6:22 PM EDT

When is it time to apply this preventer?

Hennepin County Minnesota

1 Response

Usually at the end of April, but this year may be earlier. There are two good indicators of when to put down pre-emergent. One is soil temperature. Use an inexpensive soil thermometer and put down the preventer when the soil temperature one to two inches down is 55 degrees over several days:

Second is to use what's in bloom around you. Put down the pre-emergent when the forsythia is in full bloom: