A Gardeners Forum Forums Gardening Reference Gardening in 2003 CrabGrass

Hi. We had a very late spring this year. It snowed in April! Well, around the 2nd week in April, I put down the Crabicide and Fertilizer (it was about a week after the last snow.)

Well, it fed the crabgrass - LOL. Around the first week of May, crabgrass took over part of the lawn.

I've read that crabgrass doesn't like a well watered lawn, to be shadowed in high grass, etc. I don't have too much control over the length, as a man mows for us once a week. I asked him to cut it at around 2", but he forget's to reset it (he's a nice guy, though.) So, it's cut at around 1.5"

I purchased Ortho's liquid crabicide, that it says to use with a dial-up. Has anyone used this? Does it work? I used a liquid crabicide a few years ago, and it did nothing.

Thanks for any input.

What you have may not be crabgrass, especially if it showed up in mid May. For crab grass to germinate it takes 3 nights ground ( not air ) temps of 60 + degrees. usually this will not happen until the earliest the end of may or the beginning of June. Crabgrass at this point should only be at most a inch tall, and still only in the 2 to 3 tiller stage. What you may have is quack grass, which closely resembles crab grass but perennial as opposed to the annual crabgrass, which comes back from seed each year. The crabgrass preventer works by making a vapor barrier that the new seedlings can not grow thru. A established plant coming up from the roots will not be effected.
Unfortunately if it is quack grass, it is a true member of the grass family and can not be differentiated between enough to alow a selective killer do any good. You will have to wipe it out with a round up type product and reseed the area.
This would best be done in the fall when the seedlings would stand a much better chance of survival.

Thank you, plant Doctor! I had done some reading on it a month ago, and thought that may have been it. But, I couldn't tell. Someone came to our door, offering to mow the lawn, and told my mother that *I* had put down the crabicide "too soon" and that was why we had "crabgrass." Made absolutely no sense to me, given the time I'd put it down, and when the crabgrass came up (within a couple of weeks. Since it creates a barrier, as you described, I couldn't figure *how* putting it down "too soon" would have caused them *to* grow two weeks later. If anything, it could have been too late (but, as I said, it was still very very cold. It is still unseasonably cold for this time of year for us.)

Thank you very much for your reply! I'm going to try to treat the quackgrass. If I put the round-up only on the leaves (and don't spray it), do you think that if I grow grass in a trays, it will transplant well in the spots where I kill the quackgrass? Is quackgrass overpowering to fescue (i.e., will it overtake the lawn the way crabgrass does)?

One last question, since we are having an unseasonably cool spring, should I put down another treatment of crabicide at some point this year? I had read at some site or other, that the crabicide lasts for "x" number of weeks.

Thanks, again!