View Full Version : Dethatch / Aerate Prior to Pre-Emergent Application?

03-06-2012, 09:49 AM
I have a few lawns that have had a very bad crabgrass problem last year. I know it is usually recommended to dethatch and aerate in the fall, however, it has not been done. Should I dethatch to remove all dead crabgrass and or aerate prior to my first application of Pre-Emergent? I plan to apply Lesco Dimension 19-0-6 and seed in the fall.


03-06-2012, 10:08 AM
How much open dirt will there be, rather than lawn for the summer, IF nothing grows where the crabgrass was?

03-06-2012, 11:04 AM
There is a large area of yard about 1/4 acre that was 95 percent crabgrass so it will be mostly bare dirt. The rest of the 1 acre yard is probably about 25 percent crabgrass. I was planning on starting them with 2 pre-emergent apps and a good fertilizer program with seeding in the fall. I haven't had much luck seeding in the spring, only where lawns have been well established. I tried uploading some pics of the problem area but it looks like the files are too large.


03-06-2012, 11:31 AM
Spring time is definately touchy, if there is no irrigation and we don't get decent rains, but that can happen in the Fall too, so give it a shot...

Slit seed in some quality grass seed for your area, with 10%-20% Annual Ryegrass, just as soon as the ground thaws... That is your only investment in that lawn, becuz you do not want to nremove the OM that will protect and nurture the seed and aeration is just in the way at this point...

When you are looking at that much dirt for the entire summer, you discover that there is ... nothing to lose!!! Chances are, you will succeed... :)

03-06-2012, 11:35 AM
Scratch up the bare area's and seed and starter fert NOW. Temps are conducive to germination.

Skip the Dimension on these seeded areas.

If you get good growth and this growth has to be mowed, wait till you mow it twice and try the Dimension then (Late June?)

03-06-2012, 01:47 PM
Okay, the "seed now" sounds like a better plan. There are some other completely bare areas that seeding now will make the customer much more happier than dealing with bare dirt all season.

I didn't realize that you could "spot treat" a lawn with the dimension and still grow seed on untreated areas. Probably a good 3/4 acre will get the dimension 19-0-6 and the really bad problem areas will get starter fertilizer and seed. No aeration and no dethatching. There is no irrigation so hopefully they will get some nice rain this spring.

The customer mentioned tall fescue for their lawn, however, it sounds like a good quality annual ryegrass will establish more quickly in the spring and maybe by fall I can overseed with the fescue after completing a fertilizer application program this season.

Thanks again. Any other thoughts appreciated.

03-06-2012, 02:00 PM
Here are some pics of the affected area. This area is the worst hit with the crabgrass. The rest of the yard is not too bad.

03-06-2012, 10:34 PM
Thanks SmallAxe and TLS. I spoke with the customer and they said go ahead with our fertilizer package and spot seeding. I'll seed and apply starter fertilizer to the really poor areas and apply the pre-emergent later in April to the non seeded areas.

Thanks again for your advice.

Procut lawn expert
03-06-2012, 11:54 PM
i just did a yard just like that i just put a topdress of got soil and a little sand then the start app no 19-0-6 .i would skip the 19-0-6 aerate top seed and the starter .. i post some pics of mine when it gets started good and show you what it turned out like . this is what john deere landscapes told me to do i was going to do the same thing you were .

03-07-2012, 03:15 PM
That would be great if you had some pictures. I will be doing the same thing and post some pics of the results as well.

Procut lawn expert
03-07-2012, 11:01 PM
i am hoping we get some rain tonight .so maybe in a few days it will get to going