How To Get Rid Of Crabgrass + Kill Weeds {PRO Tips}

How to get rid & kill crabgrass and weeds

The trouble with maintaining a healthy lawn is weeds that can totally smother your prized lawn camouflage themselves inside that lush, green goodness.

Fast-growing crabgrass is the enemy of gardeners worldwide for its ability to sneak into bare or weak spots in a  garden and virtually take over.

We’ll walk you through how to spot, prevent and treat a crabgrass invasion so that your lawn is the envy of the neighborhood.

What is Crabgrass?

Crabgrass is a common name for digitaria, a genus of over 300 plants and the most common lawn pest is called digitaria sanguinalis which is also known as Smooth Crabgrass or Hairy Crabgrass.

The ability of one plant (which can grow up to a foot in diameter) to sprout up to 150,000 seeds every year makes this an incredibly invasive plant.

Despite its name, crabgrass is not an actual grass but rather a very tough weed to eliminate.

Interesting Crabgrass Facts

Some crabgrass seeds (primarily those native to Africa and India called fonio) can be harvested and toasted to make flour which is then fermented into beer. Yes, crabgrass beer.

Nutritious as it is hearty, crabgrass is one of the world’s fastest growing cereals and used as a staple crop in Africa.

And, as you might imagine, golf courses fear it because it is very easily spread via foot traffic.

Birds also love to eat it while making a habit of dropping seeds everywhere as they fly above.

Here’s an argument for mowing your own lawn:  Crabgrass also spreads by getting caught in mower blades so make sure to keep them clean.

How to Identify Crabgrass?

By just taking a closer-than-normal look at your lawn, you’ll be able to identify crabgrass if you know what to look for.

Wider leave blades than the average grass and low-growing appearance is what differentiates this weed from a regular lawn, and it starts in a little clump and grows outward.

This video shows exactly what you should be looking for.

Also, inflorescence, or the finger-like branches, on crabgrass are where those pesky seeds hang out.

How to eliminate weeds in your yard

How to Prevent Crabgrass?

1. Take Care of Your Lawn

The best prevention is to maintain a healthy lawn by watering deeply, but not too frequently, and by using a slow release fertilizer as crabgrass can’t tolerate nutrient-rich environments.

2. Top with Organic Matter

In addition, consider applying a top layer of organic matter such as compost or leave grass clippings after mowing. Again, crabgrass is averse to nutrition.

3. Timing is Everything

Getting on top of the problem in the spring before the weed flourishes in the heat of summer, will save headache (remember, up to 150,000 seeds).

4. Cover Bare Spots

weed prevention

Those bare spots in the lawn, cracks in cement or dirt borders are heaven for a weed like this that relishes bare spots and distressed, undernourished lawns so keep those borders mulched.

5. Keep Blades Long

Think about the length of your lawn, because while a short lawn can help identify unwanted pests, a lawn 3 inches tall and above can choke out crabgrass naturally but prohibiting sunlight.

6. Consider Pre-Emergents

Timing is everything when applying a pre-emergent, which prohibit the germination of seeds, because if the weed is past the germination stage then it’s a pointless use of chemicals. Experts believe that because crabgrass being hard to see in early stages, many gardeners miss the window, so they advocate the healthy lawn strategy in lieu of pre-emergents.

How to Remove Crabgrass From Your Lawn?

1. Use Manual Labor

Grab a hand pick or hoe and use elbow grease to lift up patches, preferably while the soil is moist, and before the seeds germinate, but remember to immediately cover the bare spots with mulch or similar. A pick that is v-shaped at the end is most effective to surround and dig up roots.

2. Dig Deep

Make sure to remove crabgrass by the roots, otherwise it will just grow back.

3. Dispose Carefully

Be careful how you dispose of the newly-removed crabgrass to avoid accidentally spreading seeds on the way to the bin. Don’t toss it in the compost bin and consider sealing it up in a plastic bag.

4. Think About Chemicals Before Use

There is no one chemical specifically designed to kill crabgrass and those that do kill it typically leave the roots alive, which doesn’t solve the problem because it will just grow right back. This is hearty stuff that is hard to kill.

Organic Remedies

1. Boiling Water

Pour boiling water over crabgrass to kill it, but be careful as it will also burn the lawn you’re trying to save. Wear gloves and keep the kids and pets out of the splash zone.

2. Use Newspaper

In garden beds or areas where crabgrass is growing alone and there are no nearby plants to impact, use newspaper to smother it.

3. Try Corn Gluten Meal

Corn gluten meal (CGM) has been recently discovered to have pre-emergent characteristics by inhibiting root formation of germinating seeds so if the seed germinates and forms a shoot, it won’t form a root. Timing is everything when it comes to applying corn gluten meal so be sure to follow instructions and it can be expensive due to multiple applications needed. Corn gluten meal assists with dandelions and other pesky weeds, and can be found at a garden center.

4. Smother with Baking Soda

Rinse the area with water and pour a hefty dose of baking soda on the crabgrass while minimizing contact with other plants. Wait a few days and re-apply if necessary until it turns brown and dies.

5. Spray Vinegar

Store-bought household vinegar isn’t usually strong enough (at just 5%), but it is available in higher potency (20%) at farm supply or other specialty stores. Some gardeners report success with spraying a higher strength onto crabgrass until it dies and then they dig it out.

Final Thoughts…

Just like any weed, managing crabgrass requires proactive gardening. The truth is that our lawns are weaker than their enemy, weeds, and are made pure because of human intervention. It’s worth the effort,  but if you’re tired of maintenance there are plenty of alternatives, like installing pavers or artificial grass.

Photo credits: top photo collage, Flickr/Macleay Grass Man; inflorescence, Flickr/Pato Novoa; grass in asphalt, Wikimedia Commons