Question
Help!  I accidently put Scott's Turf Builder with Halt's crabgrass killer on the place where i wanted to put grasseed.  The back of bag says that you cannot plant grass seed for 4 months!  after you use the turf builder because it will damage seedings.  How can I fix this so I can plant my grass? Location is northeast ohio.

Answer
The active ingredients in the crabgrass preventer will prevent crabgrass seeds as well as regular grass seeds from germinating (sprouting). If you sow grass where you put down the herbicide, grass will not sprout.

You can instead put down sod (grass which has been grown elsewhere and cut in strips to be replaced). Sod is more expensive than seeds, however. See lable for when it is safe to put down sod (typically 30 days later, but kindly refer to lable).

You can also wait until september to sow seeds. This is anyway the preferred time of the year in Ohio to sow grass seeds. The soil is warm from summer and the cool air temperatures and return of moisture will give grass a good head start. Then the grass will get another head start next spring before having to go through a taxing summer. Therefore, seeding is preferred in fall compared to spring.

You can not sow seeds in the area where crabgrass killer has been put down. Some crabgrass killers are made with an active ingredient named siduron (tuppersan). This is the one of the only approved herbicides which allow you to sow grass seeds and fight crabgrass at the same time. However, yours are not based on this ingredient (I am guessing based on the instructions on the back which you quoted).

-- Kenneth