I was reading your article about crabgrass and on line says, 3. An area treated with crabgrass preventer should not be raked or roughed up (kids, dogs, etc.) for four to six weeks so that the preventive barrier is not disturbed. I have crabgrass in my flower bed, can I rake it and them put the crabgrass preventer on the dirt? Can I plant in that area and if I do, do I have to wait before planting?
Crabgrass comes from seed each year so, if you have clumps of grass growing already in your flowerbeds then it isn’t crabgrass but some other perennial grass that comes back from an established root system, not from seeds like crabgrass. There are weed preventers that can be used in flowerbeds that will stop weed seeds from sprouting. There’s Preen and the organic alternative Corn Gluten. You’ll need to still pull any weeds or grass that are there now and then apply the Preen or Corn Gluten. Any seeds that blow into the flowerbed (from the lawnmower for instance) won’t be able to sprout through the barrier of Preen or Corn Gluten. If you dig or scratch up the surface of the flowerbed it breaks the barrier and seeds WILL be able to sprout and grow. Wait to apply your weed seed preventer until after all your planting is completed. Peter Bowden