Crabgrass preventer (when to apply)

atoner – posted 19 March 2004 17:25

I’ve got a bag of Scotts fertilizer with crabgrass preventer just waiting to go down. We’ve only had a couple days in the 70’s here in Winston-Salem, NC so far, and 60’s are forecast for this week.

The bag says to apply Feb-Apr, before temperatures are in the 80’s. Scotts’ web site says to apply before May in my area and that crabgrass will start to germinate when the temperature is about 60 for 4-5 consecutive days.

Should I apply now or wait a couple weeks? There are a few spots in the yard where I’d like to try and get some grass seed to germinate, but I probably can’t afford to wait until it is up established.

Thanks.

ted – posted 19 March 2004 20:22

pre-ems are concerned about soil temps, not air temps. probably need to wait a little while . didn’t understand the comment about the grass seeding- pre-ems and grass seed DO NOT mix! don’t lose too much sleep over it- the products homeowners can buy are so watered down anyway…..remember pre-ems are effective for a couple of grassy weeds anyway, and not for a very long period of time- they all break down when temps hit the 90’s.

cohiba – posted 20 March 2004 07:23

As an informal indicator we use the forsythia bush. We apply conventional PreM when the flowers of the forsythia start to drop off. Remember, flowers and weeds, insects, etc. are all dependent on soil temperatures. If you are concerned about length of effectiveness try a split application, 1/2 rate now. 1/2 rate in a month or so. There is only one PreM that has seedlings on its label, Tupersan. I don’t know if it is available to the homeowners. Dimension is a great pre-post crabgrass preventer and can be applied later in the spring. allowing and early seeding and a late crab preventer. But has little to no effect on Goosegrass.

Good Luck…….

ted – posted 20 March 2004 21:17

good advice. tupersan can’t be bought by homeowners. it’s also not a very good pre-em.