Hardiness Zone: 5b
Vanet from Saugerties, NY
I cannot think of any easy solutions to controlling crabgrass, and I'm not sure a person can hope to ever get rid of it completely. Even when using pre-emergent herbicides, it seems to come back eventually. The first thing that I would suggest is to raise the height of your lawn mower blades to 3 inches. This will support the healthy growth of turf grass and leaves less room for crabgrass seeds to take hold.
For long-term control, I would recommend applying corn meal gluten. This is an all natural by-product of milling corn that acts are a pre-emergent for controlling crabgrass, barnyard grass, foxtail, dandelion, lambs quarters, pigweed, purslane, smartweed and others. If applied once in mid spring (around the time the lilacs bloom) and again in mid August, you should catch two different flushes of crabgrass. A third flush will probably be ready to germinate just in time to be killed off by frost. Corn meal gluten should not be used if you're trying to establish a lawn, because it prevents regular grass seed from sprouting too. If you apply this at a rate of approximately 20 lbs per 1000 sq. ft. the first year, you should see at least a 40-50% reduction in crabgrass. Control will continue to improve each year with successive use.
I think the men mowing also "seeded" my yard-- however I made it worse by agreeing to "scalping" in preparation for summer growth. Will never do that again. The grass didn't have the strength to fight off the weed seeds. The other thing I did was insist the height of my grass to be at least 3 inches before mowing-- we'll find out if mine is OK next spring.
Vanet I had read this you might give it a try
A great organic "weed and feed" product is corn gluten. It will suppress crabgrass germination, while fertilizing your lawn.
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