Crab grass preventer- what temp does it need to be?

[Butterfly4u]

Whatsthenews,
check out this link.
Look for forsynthia bushes in bloom in your area when you are driving around, then apply the following week.
Getting Rid of Crab Grass | Pictures | How to Kill Crabgrass

[SD4020]

Originally Posted by Whatsthenews

OK- so once there is no more frost?
Our ground doesn't really freeze much below the surface when there's a ground frost, and that will be gone usually by afternoon as most days are sunny and above freezing.Plus very dry air.

I notice that chickweed and wild strawberry never seem to die!
Certainly we have them now, but we are starting to get days in the 50s/60s but then back down into the 40s again, with some nights still below freezing.

I desperately don't want to be too late in putting it on.
I'm on a mission this year to get rid of the stuff

Soil temperature wont be to contingent on frost or anything like that.

Soil Temperature Map
Soil Temperature Regimes Map | NRCS Soils

Always follow the label's instructions for application. It will include rates, when to apply and all that good information.