How To Kill Crabgrass Naturally In The Organic Lawn And Garden

Organic gardeners can kill annual lawn weeds like crabgrass without chemical herbicides. Get rid of crabgrass with cultural controls and organic sprays.

Even those who aren’t sure what crabgrass looks like or whether their lawn is afflicted with it know that these grass weeds are a pestilence in the landscape. In the spring, it’s difficult to miss the crabgrass killer advertisements one hears on the radio and television, a call to arms that gardeners can’t afford to ignore. What can gardeners who eschew chemicals in the lawn and garden do to get rid of crabgrass? The answer is plenty.

Identify Crabgrass

Crabgrass actually refers to a genus of annual plants that encompasses approximately 300 species of grassy weeds. The varieties of crabgrass common to North America can grow as tall as three feet, but the plant is very adaptable and can still form seeds when the mower keeps it short.

Gardeners with thin or struggling lawns can recognize these thugs sending their spreading stem clumps and fingerlike seed spikes growing from summer to fall. The leaf blades may appear bluish or purplish green, and the plants can be smooth or hairy.

Cultural Crabgrass Control

get rid of crabgrass

Gardeners who have a minimal crabgrass problem can control it by increasing the vigor of their lawns. A thick, healthy lawn can prevent crabgrass from germinating by shading the seeds. Mowing grass no shorter than 2 to 3 inches strengthens turf grass by providing more plant surface to engage in photosynthesis, and also keeps the sun from triggering growth in weed seeds.

Proper irrigation can influence crabgrass growth in the lawn. Organic gardeners should strive to water the lawn infrequently and deeply, applying one inch of water to the lawn weekly, which encourages deep grass roots.

Applying organic fertilizers to the lawn during the growing season can increase the vigor of the turfgrass to the point where it will crowd out the crabgrass. An application of finely screened compost promotes healthy grass at any time during the growing season. Gardeners can put down fish, blood, and bone meal in the early spring and summer to provide slow-release feeding during these peak growing times.

Organic Crabgrass Preventer

Organic gardeners can apply corn meal gluten in the spring and in the fall to stop crabgrass from germinating. This natural corn byproduct stops all seeds from germinating, including turf grass seeds, so gardeners shouldn’t apply it at the same time they are reseeding their lawns.

Crabgrass Control in the Vegetable and Flower Garden

Ornamental beds with inadequate mulch are ripe for an invasion of crabgrass. A 3-inch layer of organic mulch not only suppresses the germination of crabgrass, it makes established weeds easier to pull. Gardeners should dispose of crabgrass weeds rather than placing them in the compost bin, as the seeds can stay viable for up to three years if the bin doesn’t generate enough heat to destroy them.

Organic Weed Killer

Weed killer is the most efficient approach to kill crabgrass. Several treatments on the market are made entirely of natural chemicals and are quite efficient in weed control. Natural Armor Weed and Grass Killer, for example, is made with all-natural components that are safe for dogs and children. Simply spray the weeds individually with the product, and it will shrivel up.

However, keep in mind that some of these solutions may destroy any grass they come into touch with, so handle overgrown areas with caution.

Boiling water

When you sprinkle boiling water on an area of crabgrass, the plant is stunned and dies immediately. Pour the water in a broad circle around the weeds, allowing the hot liquid to permeate the whole root system and effectively destroy the entire patch.

Because boiling water will destroy any plants or grass near the weeds, this approach is best employed in areas where weeds have overrun and taken over the whole area.


Vinegar is a wonderful natural material with several applications in the home. It’s unsurprising that it has applications in your yard and garden. Vinegar, which is all-natural and safe for children and dogs, can successfully eradicate any vegetation, even crabgrass. Most importantly, unlike many chemical treatments, it will not harm or render your soil unusable.

Simply soak the whole marijuana in vinegar with a 5 percent or greater acidity level. You may not notice effects right away, but if you repeat the technique multiple times over the course of two weeks, the crabgrass should finally wither and die.


Smothering the weeds is an effective way to deal with huge regions of crabgrass. Suffocating them shuts off light and destroys the crabgrass patch in 4-6 weeks.

Place large, heavy objects, such as stones or bricks, on top of the crabgrass and leave the area alone for several weeks. You can easily take out the crabgrass and transplant grass seed once it has died.

Naturally preventing crabgrass

The next logical step after eradicating your crabgrass problem is prevention. The key to preventing another crabgrass invasion is to create lawn conditions that hinder germination and development of the weed.


Crabgrass is a water-loving weed that thrives when irrigated often. Water less often but with a larger volume to support healthy grass growth while suppressing these weeds with weak roots. This will encourage your grass to grow, while the weeds will struggle and eventually die.


We want to keep our grass short so that we don’t have to mow it for a time. This strategy not only saves you time and work, but it also produces ideal circumstances for weed development on your grass. Weeds get more sunlight and have more area to extend their roots and invade when grass is cut short.

Keep your lawn relatively long to help avoid crabgrass development, and only cut 1/3 of the blades at a time.


“Overseeding” is a fantastic way to avoid crabgrass development. Plant a lot of grass seeds on your lawn in the spring so that it crowds out any weeds that are sprouting.


It may seem obvious, but failing to weed on a regular basis encourages weeds to thrive and take over your grass. Weeding on a regular basis maintains the weeds young and manageable, allowing them to be readily uprooted.

Most weeds are easy to control, but crabgrass is a kind of plant that is particularly invasive and spreads fast. Crabgrass control is critical for maintaining a nice lawn. While keeping your lawn might be a time and energy draining task, it will be well worth it once you can admire its pure beauty.