We have had an early warm spell followed by a hard freeze, in the teens several mornings. Will the freeze kill any crabgrass that has germinated and sprouted? Should I wait until soil temps warm again for crabgrass preventer or apply ASAP?
Early Warm Weather and Crabgrass Germination
Certified GKH Gardening Expert
The frost is not likely going to kill the Crabgrass.
Spring is a good time to apply selective herbicides.
Check with your local County Extension Office for advise on weed control in your region.
Here are some links with more information.