I am reseeding an area of the lawn. I have killed the crab grass and now a lot of chick weed shows up. I will over seed but in the future what do I do to eliminate this problem? It is pretty dense. I am aware that when new grass is planted I cannot use chemicals. I will put down pre emergent in the spring for crab grass but this won't do for the chickweed.
We recommend that new grass seed be put down by the middle of October in order to have time to establish before harsh weather sets in.
You can pull or hoe up the chickweed. You can also use a slit seeder machine to put down the seed, which would cut rows through whatever weed or dead weed material it there. (Use a mower at the lowest setting to help remove all the dead organic matter, if that's possible. Then rake it off.)
In the spring, look for a crab grass preemergent that has the ingredient Pendamethalin. This product will also prevent some broad-leaved weeds from germinating. (READ the label for what weeds specifically it will prevent.)
Will the Pendamethalin take care of crab grass? In the past I had used Southern States brand of Preen for crabgrass plus other weed control. Thanks again!
Yes, pendimethalin will prevent crabgrass germination. If chickweed has been a perennial problem,you can apply a fertilizer containing the preventative herbicide called gallery in early September.