Fortunately, we have had no problems with crab grass.
Unfortunately, that means I have no self-tested solutions to tell you about when it comes to getting rid of it.
I do have this recipe called WEED BE GONE:
1 Gallon of vinegar
2 cups of Epsom Salts
1/4 cup of Dawn Dish Soap
Advertised to kill anything you spray it on.
Spray in the Morning and it’s dead by dinner time.
Greeneyes! Anything you spray it on! Works on squash bugs and takes out the zucchini too!
Yes, that’s a great weed killer that doesn’t harm beneficial pollinators and other insects.
If you want instant gratification, use boiling water. Bit tricky carrying the kettle out to the garden, but worth it. Works great on the patio too, where the weeds like to come up between the bricks.
I made up a small batch of your Weed Be Gone and it seems to work....going to make up more.....