How Do I Control Crabgrass or Tall Fescue?
- 1). Remove the patches. One option is to physically dig them up. Use a trowel or shovel to remove the weed patches and all of their underlying roots. Another option is to spray the actively-growing weeds with glyphosate herbicide (like Roundup) according to the manufacturer's instruction.
- 2). Fill in the bare spots left behind with grass seed or sod.
- 3). Treat your lawn with corn gluten meal in mid-April. Crabgrass spreads primarily by seed, which can last up to 3 years in the soil. Corn gluten meal kills crabgrass seed. It is also a nitrogen-rich fertilizer. If the culprit is not crabgrass, you're still doing your lawn a favor. Use a broadcast seed spreader (follow the instruction manual for your make and model) to spread 15 pounds of corn gluten meal per 100 square feet of lawn. Water the lawn with a few inches of water immediately after to help it penetrate the soil. Then withhold water until the top inch or two of the soil dry out. Repeat annually if you see any new weeds pop up during the growing season.
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