When is the best time to use crab grass treatments?

[Kim1414]

I had a big problem last year with crab grass taking over our lawn. We have a very large lawn area and I can not control it by pulling the weeds out by hand. I need a large scale fix to the problem. I have been reading about crab grass killer that gets spread on the lawn and prevents the crab grass seeds from sprouting. How do I know when to apply this to our lawn for the best results?

 

[LIcenter]

I had a big problem last year with crab grass taking over our lawn. We have a very large lawn area and I can not control it by pulling the weeds out by hand. I need a large scale fix to the problem. I have been reading about crab grass killer that gets spread on the lawn and prevents the crab grass seeds from sprouting. How do I know when to apply this to our lawn for the best results?

The optimum time to put down a pre-emergant weed killer is early spring after the ground has thawed completely. (Many states now have laws about applying any type of fertilizer or weed killer on frozen ground, so just be aware of that.) Normally I will also hit it again about a month after the first application @ half the recommended rate. If you have heavy rains after your first app. Apply second app. @ the full recommended rate. A word of note.... When you see pre-emergent in the store, Buy it! This is not an item that gets re-stocked, and sells very fast.