Don't get crabby, get even
If you have bunches of unsightly grass popping up across your lawn, you might be facing a dreaded crabgrass infestation. The good news: You can learn how to get rid of crabgrass for good. The bad news: this invasive weed is a tough one to eradicate. These steps will help you become a crabgrass killer.
Crabgrass is a weed imported into the United States as a forage crop back in 1849. It soon became an invasive weed that can easily outcompete native grasses (i.e., choke out your perfectly manicured lawn). The problem with crabgrass is that a single plant can grow 150 to 700 tillers and produce 150,000 seeds—and these seeds can remain dormant in the ground and pop up year after year.
Not only is it unsightly, but crabgrass is also bad for your turf. It can take over and kill your lawn by preventing it from getting the water, sunlight, and nutrients it needs to thrive.
Even though crabgrass is an annual plant, don’t be fooled: when it dies off in cooler weather, it leaves behind thousands of seeds waiting to germinate the following spring. In other words, crabgrass removal requires a long-term strategy. You can’t just pull the weeds by hand. You have to attack the seeds.
You’ll be able to distinguish crabgrass from other, healthier grasses because it looks vaguely like a crab—like the name indicates. This invasive weed grows low to the ground and has branching blades that radiate from the center of the plant, giving the appearance of crab legs. You’ll also notice that the blades are thicker than typical turfgrass and similar weeds. They’re about the thickness of a pencil, but it depends on the plant's maturity.
Another tip-off is location. Crabgrass most commonly grows in damaged areas of your lawn. Think of it as a squatter—if there’s vacant space, it’s moving in. If you notice thick-bladed clumps of grass in thin areas of your turfgrass, it’s probably crabgrass.
Removing crabgrass requires a two-pronged approach: first, you need to get rid of the weeds. Then, you need to prevent their seeds from germinating. Follow these steps to achieve crabgrass control.
Depending on the removal method, you may need different tools and supplies to rid your lawn of crabgrass for good. Below is a breakdown of what you’ll need based on your removal approach.
Removing by hand:
Weeding tool
Gardening gloves
Garbage bin or bags
Grass seed
Garden hose
Removing with herbicide:
Pre-emergence herbicide
Post-emergent crabgrass herbicide
Lawn spreader
Grass seed
The most natural way to kill crabgrass is by tackling it early, by hand. Though laborious if your yard has lots of crabgrass, a yard with mild crabgrass can especially benefit from this simple removal process without herbicides.
Make sure the grass is damp—preferably after rainfall or after you’ve watered it with a garden hose.
Wearing gardening gloves, use a weeding tool to yank up the crabgrass.
Double-check for any leftover roots.
Discard the weeds in a trash bag or green recycling bin.
Plant new grass seeds or add mulch to the patchy sections of your yard.
Avoid tossing crabgrass into your compost, as its seeds can germinate and spread to your lawn again—defeating all of your hard work.
If you feel like the crabgrass is winning the battle, it may be time to consider an herbicide or a crabgrass killer. Many different brands are available at garden centers and home improvement stores, but if you’re dealing with existing crabgrass plants, you’ll want to use a post-emergent weed control. You can use this product whenever you see new bunches of crabgrass emerge, but keep the following in mind:
Choose a chemical herbicide labeled specifically for crabgrass. General herbicides designed for weeds will not be effective against crabgrass and could damage your lawn.
Look for a liquid herbicide that contains the ingredient Quinclorac.
Use a crabgrass herbicide as a spot treatment vs. an all-over grass application.
Apply chemicals according to the manufacturer’s directions, and keep pets and children away.
If you’ve already worked hard to remove crabgrass and want to take preventative action using herbicides, you can also use a pre-emergent herbicide designed for crabgrass. Pre-emergent crabgrass killer tackles crabgrass before it has a chance to emerge. You’ll find the biggest success if you apply a pre-emergent herbicide in early spring before crabgrass seeds start to germinate.
This herbicide comes in granulated form and is best applied using a lawn spreader—but again, follow the manufacturer’s instructions when applying herbicide.
Sometimes, even a herculean hand or powerful at-home herbicide won’t successfully eradicate this pesky weed. In this case, your best bet is to take a multifaceted approach. Try out all of the following methods to defeat crabgrass once and for all.
Hand-pull crabgrass as soon as they emerge using a hand weeder tool.
Apply crabgrass herbicide before the crabgrass flowers.
Reseed your lawn with the right grass for your region in late summer or early fall.
Call a local weed control service if your yard continues to have crabgrass in the following spring.
Having a solid removal strategy is paramount to warding off this stealthy weed. By applying these crabgrass removal tips, you might keep crabgrass out of your yard for good.
Since crabgrass is an annual with seeds that can survive year-to-year, time is of the essence. The longer crabgrass grows, the larger and more tenacious it will become. You don’t want to allow new weeds to germinate. Instead, pull the weeds—including the roots—as soon as you notice them.
Once you know what to look for, being proactive is the best strategy against crabgrass getting out of hand. Pull any crabgrass as soon as you see it, ideally before it has a chance to disperse any seeds.
When it comes to crabgrass control, a hand weeder is your best friend. This essential gardening tool pulls crabgrass out by the roots using either a small claw or a spiked plunger. Carefully use the tool to dig beneath the plant's roots and remove the crabgrass. Make sure you’re not leaving any portion of the weed behind, or it will grow back.
To ensure you’ve completely removed the entire plant, you can also pour boiling water as a DIY weed control method. Avoid pouring boiling water over plants you want in your yard, as it will kill all plants.
When left out in a yard, crabgrass seed heads (which look vaguely similar to Bermuda grass seed heads) are a ticking time bomb. It won’t be long before the plant finds a way to spread. To prevent weeded plants from re-rooting or germinating, it’s best to dispose of your crabgrass in a sealed trash bag.
Crabgrass removal isn’t a one-and-done process. Even though this weed is annual, crabgrass produces thousands of seeds that can germinate the following growing season. It can take a few years to rid your lawn of crabgrass entirely. Just keep weeding your lawn and taking preventative measures until it’s gone for good.
The cost of weed removal is generally between $35 and $125, but preventing crabgrass regrowth requires ongoing lawn maintenance. Expect to pay $100 to $250 for seasonal maintenance, plus $50 to $200 for monthly upkeep.
While stooping around your yard and pulling up stubborn crabgrass can make for a good workout, it’s safe to say most homeowners don’t enjoy tackling this pesky weed. Preventing crabgrass can save you time and energy—all while keeping your lawn beautiful. Follow these steps to prevent crabgrass from invading your lawn.
Cool-season grasses are particularly vulnerable to crabgrass. This weed thrives in warm, sunny weather that stresses cool-season grasses out. If you’re struggling with crabgrass, warm-season grass may be a better option (climate permitting).
Because crabgrass thrives in areas of your lawn where there is damaged or thinning grass, the best way to prevent crabgrass growth is to maintain a healthy lawn. You can follow this lawn maintenance checklist to make sure you’ve got every angle covered.
Keeping your grass on a regular feeding schedule means your grass will grow fat and happy—well-fed grass leaves fewer opportunities for crabgrass to thrive.
But you may want to avoid fertilizing in the summer. Crabgrass tends to benefit more from fertilization in high temperatures than many popular turfgrasses. Follow the best practices for lawn fertilization, but avoid feeding your lawn during the height of summer.
You may feel compelled to mow crabgrass to oblivion, but this weed can produce seeds at heights as low as ½ inch. Instead of giving your lawn a close crop, raise your mower to a height of 2 to 3 inches (depending on the turfgrass species). Taller grass helps shade your lawn, keeping it cool and moist. Crabgrass can’t germinate in cool conditions.
Instead of vigorously raking your lawn after every mow, leave the grass clippings. They’ll give your grass nutrients and help prevent new crabgrass seeds from germinating.
Remember, this is a delicate balance. You don’t want thatch buildup to choke out your lawn. If your lawn is prone to thatch buildup, consider hiring a local dethatching service to remove the thatch once a year during the growing season.
Giving your turfgrass a healthy dose of water can promote the type of root growth that outcompetes crabgrass. So, how much water is right for your lawn? Starting in early spring, when crabgrass starts germinating, give your grass an inch of water every week and allow it to soak deeply into the soil.
You may need to increase watering as the weather gets warmer. Crabgrass can tolerate extreme temperatures, and you don’t want your grass to dry out and leave your lawn vulnerable.
Whether from pet urine or a summer scorcher, your lawn will inevitably have some spot damage. Crabgrass will use this as an opportunity to move in and get extra cozy. It’s imperative that you repair your lawn by removing damaged or dried patches as soon as you notice them. Also, overseed thinning grass or bare areas right away.
To stop dormant crabgrass seeds from germinating, use a pre-emergent herbicide in early spring. Apply when the soil’s surface temperature reaches 55 degrees Fahrenheit for about four consecutive days. You can plant forsythia as a marker. When forsythia blooms, it’s time to apply pre-emergent.
Tara Dudley, Expert Review Board member, landscape designer, and owner of Plant Life Designs, says to plant forsythia in your yard as an indicator plant. “When this is blooming in early spring, you’ll know it’s time to apply your pre-emergent for crabgrass,” says Dudley.
If your grass seems more crabby than most, or lawn care is taking up too much of your time, consider hiring a local lawn care repair professional who can help restore your lawn to its former green glory. For best results, you need to work with someone experienced who can help you recognize and prevent threats.
The main problem with crabgrass is that it produces thousands of seeds that can remain dormant until the following season. To get rid of it, you have to remove existing plants before they have a chance to spread seeds and stop old seeds from germinating.
Crabgrass is very resilient, and homemade solutions like vinegar may not be strong enough. Typically, hand-weeding is the most effective option that doesn’t involve harmful chemicals. You can use corn-meal gluten as a natural pre-emergent herbicide, but it’s not as effective as chemical weed killers.
The best time to fight crabgrass with pre-emergent herbicide is when forsythias tend to bloom. In the mid-Atlantic region, this is usually between April and May. Even if you're late to apply the herbicide, it’s effective as long as the crabgrass plant has fewer than five leaves.
A spot herbicide for weed control is effective at killing crabgrass and not grass, but it depends on the type of herbicide. Always check the label to ensure that your herbicide is safe for grass but tough on crabgrass. Overall, spot treatment is ideal because it puts fewer herbicides into the soil, which can damage the soil. If you’re wanting a natural remedy to crabgrass that also won’t harm surrounding grass, you can also hand-remove crabgrass or even pour boiling water or 5% vinegar over crabgrass as a spot treatment.
