Tenacity does ok I think quinclorac does better and cheaper. Trimmed is only a broad leaf weed control and won’t touch crab grass. We put down two rounds of preemerfent, may first and June first here. If you have any bare spots in the yard it won’t matter you will still get crab grass as soon as the soil cracks. Best control is thick grass and keeping soil moist

My neighbor put out crab grass preventer this year, but it didn't seem to do any good. Strange.

Depending on the size of the area you’re dealing with, there’s a herbicide called “drive” that I’ve used in the past that works well, but it’s fairly expensive and takes a fairly heavy rate if I remember right. If you just have areas that need spot treated, Roundup has put their label on a pure crabgrass only killer that you can buy by the gallon and it even comes with its own battery powered remote. It’s in a orange and white jug at Home Depot and labeled as roundup crabgrass killer. This stuff works better than anything I’ve ever used. In about 3 or 4 days after treatment, your crabgrass will turn pure white, and then die off for good. Really great stuff if you don’t have a huge area to cover.

Tenacity

Horticulture vinegar from Amleo.com.

From researching and experience crab grass preventer needs to be put down in late March or early April on your lawn. A second treatment in June can be beneficial for the LATE emerging crab grass. Preventer type treatments only work for about 3 months. Different species of crab grass germinate at different times during the spring/summer. A preventer application coats the existing seeds and prevents them from germinating.

I used to put pre-emergent out in Feb and March. I lived near the N.C. coast then.

Put out some Cimarron plus for fire weed and it killed that no problem and turned the crabgrass yellow will see if it dies!

I have been using Trimec Plus the last applications. If one reads the label one finds salts of 2-4 D and Dicamba and other salts, so I can see why some of the other remedies had some impact.
I have not been one to do this earlier and that may be an issues. I usually wait to see the clusters and then spray. I spray at night as this product should not be used at over 80 degrees on bluegrass. Most of the mid to late summer that is an issue.
The product works well enough so I don't apply every year and that maybe an issue as well. I have noticed that I am getting patches that seem to follow along with my lawn mower. I just started using a rider 5 years ago, prior to that with my push mower I did not see that pattern. Applying two weeks apart seems to really set it back.

Bryce

A man in N.C. put Trimec in Cool Aid. Killed his wife and all his children. Happened in Halifax Co about 25 years ago.

Used here on cotton. Probably works on some weeds. 2-4-D is for broadleaf plants. Doubt it will work on crabgrass in July.

I use to do commercial spraying 95% of people that claimed they had crabgrass had something else make sure what you have before you decided what to do or spray get a hold of an extension agent.

I have section.of crabgrass creeping charlie in my carriage way that has completely taken over. I'm going to gly the whole thing and frost seed.

I will continue to use chemicals but I can see by waiting too long I have not helped myself. I need to be at this earlier in the season, even before the dandelions if I don't get them taken care of in the fall.

Bryce

I will continue to use chemicals but I can see by waiting too long I have not helped myself. I need to be at this earlier in the season, even before the dandelions if I don't get them taken care of in the fall.

Bryce

Actually if you spray 2-4d or dicamba products in high heat and at very high rates they can kill all grass, brush, and most other things they come in contact with. Also 2-4d is a growth regulator it just speeds it up, it makes the cells grow so fast they explode and kills the weeds.

Its all in prevention. I live next door to the "king of crabgrass" as I call him. No post emergent chemical worked well for me so this year I started using pre-emergent and it has worked great. I use granular Prodiamine .38% twice in the spring on the lawn next to my neighbor. You have to apply at two certain soil temps for it to be effective. Dont remember what they were off the top of my head.

Soil doesn’t have to be a certain temp, just needs to be down before crabgrass germinates which is about 55 degrees. After that you can’t let the soil crack or have bare spots, the barrier will break and crabgrass will find it

If you have a Bermuda grass lawn a light rate of round up will kill crabgrass and sand burs and just burn the Bermuda a bit.

I don't know when crabgrass goes to seed, but I suppose mowing it before that happens is important.

Is that the same thing as Timic like they put on cotton around here?