How to Get Rid of Crabgrass

Crabgrass is an aggressive, fast-spreading weed that thrives in the very conditions that often stress your lawn: hot, dry weather and compacted soil. The presence of crabgrass leaves homeowners questioning how to get rid of crabgrass and how to keep it away. Left unchecked, crabgrass can dominate your yard, outcompeting healthy grass for essential resources like sunlight, water, and nutrients. In this guide, we’ll walk you through everything you need to know about how to get rid of crabgrass and everything you need to know about the weed.

What It Is and Why It's a Problem

Crabgrass is a common and persistent weed that can be a frustrating issue for many homeowners and gardeners. As warm-season annual grass, it thrives in hot, dry conditions and can quickly take over lawns if not properly managed. Unlike turf grass, crabgrass grows low to the ground, spreading out in a mat-like fashion. This invasive plant not only disrupts the uniform appearance of lawns but also competes with other grasses for nutrients, water, and sunlight. Because of its aggressive growth habit and ability to crowd out more desirable plants, crabgrass is often considered one of the most problematic weeds for maintaining a healthy lawn. Understanding how crabgrass spreads and knowing the best practices for how to get rid of crabgrass and controlling it are essential steps in maintaining your lawn.

Defining Crabgrass

Crabgrass (scientifically known as Digitaria spp.) is a warm-season annual grass known for its rapid growth and aggressive spreading habits. Biologically, it thrives in hot, dry conditions, making it a formidable competitor in lawns during the summer months. Crabgrass typically germinates in late spring to early summer when soil temperatures reach about 55°F and continues to grow throughout the warm season. Its low-growing, mat-like structure allows it to spread horizontally, forming dense patches that outcompete nearby grass.

Additionally, crabgrass produces an extensive root system that anchors it firmly into the soil, enabling it to survive in compacted and nutrient-poor environments. One of its most problematic traits is its prolific seed production; each plant can produce thousands of seeds that lie dormant in the soil over winter, ready to germinate the following year. This combination of rapid growth, spreading ability, and persistent seed bank makes crabgrass a challenging weed to control.

How Crabgrass Harms Your Lawn

Crabgrass poses a significant threat to lawn health by outcompeting desirable turf grasses for essential nutrients such as water, nutrients, and sunlight. Its aggressive growth habits enables it to quickly dominate areas of a lawn, leading to patchy spots where the crabgrass crowds out turf grass. This disrupts the uniformity and overall aesthetic of the lawn. Moreover, crabgrass roots grow shallowly, which can weaken the soil structure, making it more susceptible to erosion. As crabgrass spreads, it leaves less room for healthy grass to establish, reducing the lawn’s density and resilience against other stresses. Lastly, because crab grass is an annual plant that dies off in the fall, it leaves behind bare patches that can be vulnerable to further weed invasions and erosion.

Common Misconceptions About Crabgrass

There are several myths surrounding crabgrass that can lead to ineffective control efforts when researching how to get rid of crabgrass. One common misconception is that crabgrass is a perennial weed that returns from the same plant each year. In reality, crabgrass is an annual weed that dies off each winter, but its seeds can survive in the soil for several years, leading to new infestations. Another myth is that mowing your lawn short will help control crabgrass, but this actually encourages its growth by giving it more sunlight and space to spread.

Additionally, it’s often believed that once crabgrass has sprouted, it can be easily eliminated with a single treatment. However, effective crabgrass control often requires a combination of pre-emergent herbicides, regular lawn maintence, and targeted post-emergent treatments to prevent its spread and return.

Natural Methods to Get Rid of Crabgrass

As we learn more about the effects of chemical herbicides and homeowners are steering away from harsh chemicals, the question of how to get rid of crabgrass naturally is a common concern. Thankfully, there are several eco-friendly methods that can effectively combat crabgrass while preserving the environment. In this section, we’ll explore natural approaches to crabgrass removal, focusing on techniques that prioritize soil health, encourage robust grass growth, and minimize the need for chemical interventions.

Using Mulch and Ground Cover

Mulch and ground cover are effective treatments when exploring how to get rid of crabgrass, as they provide a natural barrier that helps prevent this invasive weed from taking root. By covering the soil, mulch blocks sunlight from reaching crabgrass seeds, inhibiting their ability to germinate. Organic mulches like wood chips, straw, or compost are particularly effective, as they not only suppress weed but also enrich the soil as they break down, promoting healthier lawn growth. Ground cover plants, such as clover or creeping thyme, can also be used to crowd out crabgrass by occupying space that might otherwise be vulnerable to weed invasion. These plants create a dense, living layer that shades the soil, making it harder for crabgrass to establish itself.

The Benefits of Vinegar as a Natural Herbicide

Household vinegar, particularly when used in its stronger, more concentrated forms, can be an effective natural solution when determining how to get rid of crabgrass naturally. The acetic acid in vinegar works by desiccating the leaves of the weed, essentially drying them out and killing the plant. For the best results, it’s important to apply vinegar directly to the crabgrass on a sunny day when the plant is actively growing, as heat will enhance the vinegar’s effectiveness. To avoid damaging surround grass or plants, use a spray bottle to target only the crabgrass.

Additionally, applying vinegar early in the season when the weed is young and small is also more effective. However, because vinegar doesn’t penetrate to kill the roots, multiple applications may be necessary to fully eliminate the crabgrass.

Manual Removal Techniques

Manually removing crabgrass is an effective and eco-friendly method, especially when infestation is limited. The best time to tackle this task is early in the season, ideally in the spring, before the crabgrass has a chance to mature and produce seeds. Wet soil makes the job easier, so consider planning it after a rainfall or watering your lawn beforehand to soften the ground. Use a weeding tool or small garden fork to loosen the soil around the crabgrass, ensuring you remove the entire root system to prevent regrowth.

For larger patches, a hand trowel or spade may be necessary. It’s important to be thorough as crabgrass can quickly reestablish from any leftover roots or stems. Regularly inspecting your lawn and promptly removing any new sprouts will help keep crabgrass under control. Get an instant price with LawnGuru to take care of your lawn care maintenance and further prevent crabgrass from re-entering your lawn.

Preventative Measures to Keep Crabgrass Out of Your Lawn

To keep crabgrass away once removed, preventative measures are key to maintaining a weed-free lawn. One of the most effective strategies is to focus on strengthening your lawn through regular maintenance. A dense, healthy lawn will be more resilient against weeds and naturally crowd out crabgrass. Regular lawn maintenance includes consistent mowing, proper watering, and applying a pre-emergent herbicide. You can compound regular lawn maintenance with additional treatments such as aeration and overseeding in the fall, this will help fill in any bare spots and reduce the chances of crabgrass reestablishing itself.

Best Practices for Lawn Mowing

When researching how to get rid of crabgrass and how to keep it away after removal, maintaining the proper mowing height and frequency is a crucial strategy. When grass is mowed too short, it weakens the turf and exposes the soil to more sunlight, creating the perfect conditions for crabgrass seeds to germinate and thrive. By keeping your grass at the recommended height for its specific type, typically around 3 inches, you allow the turf to develop deeper roots and create shade over the soil. Additionally, mowing frequently enough to remove only one-third of the grass blade at a time reduces stress on the lawn, further supporting its density and resilience.

The Role of Fertilization in Crabgrass Prevention

A well-fed lawn is better equipped and more likely to outcompete crabgrass, as it has the strength and density needed to resist weed invasions. Proper fertilization provides essential nutrients that promote vigorous grass growth, allowing your lawn to develop healthy, thick grass. Regular feeding also helps your grass recover from stressors like drought or foot traffic, making it more resilient.

For optimal results, follow a fertilization schedule tailored to your grass type. Generally, cool-season grasses benefit from fertilization in early spring, late spring, and fall. While, warm-season grasses thrive with fertilization in late spring, summer, and early fall. Applying a slow-release fertilizer is deal, as it provides a steady supply of nutrients over time.

Overseeding as a Preventative Measure

Overseeding your lawn is an effective way to fill in bare or thinning areas, which are prime targets for crabgrass to take hold. By introducing new grass seed into these vulnerable spots, you encourage the growth of healthy turf that can outcompete weeds. Overseeing thickens your lawn by increasing the density of grass, making it harder for crabgrass seeds to find the open soil and sunlight they need to germinate. Additionally, overseeding can be used as an eco-friendly approach prevent crabgrass and further benefit your lawn by using organic lawn care products. Further information on the benefits of organic lawn care products can be found from Connecticut’s Department of Energy & Environmental Protection.

Fall is typically the best time for overseeding, as cooler temperatures and increased rainfall provide ideal conditions for grass seed to establish. Before overseeding, it’s essential to prepare the lawn by aerating the soil and removing any debris to ensure good seed-to-soil contact. After spreading the seed, keep the area consistently moist until the new grass is well-established.

Conventional Methods: How to Get Rid of Crabgrass Without Killing Grass

For those wondering how to get rid of crabgrass without killing grass, chemical treatments and traditional methods can offer effective solutions when used correctly. Pre-emergent herbicides are a key tool in preventing crabgrass from sprouting in the first place, and applying them in early spring before the weed seeds germinate can significantly reduce crabgrass outbreaks. These products for a barrier in the soil that stops crabgrass seeds from growing, without harming established lawn grasses.

If crabgrass has already taken root, selective post-emergent herbicides are designed to target crabgrass while leaving your lawn intact. These treatments work best when applied to young, actively growing crabgrass in the early stages of development. Always follow label instructions carefully to avoid damaging your lawn, and consider spot treating affected areas rather than blanket spraying to minimize chemical use.

Selecting the Right Herbicide

When choosing herbicides to specifically target crabgrass without damaging other grass types, it’s crucial to select products labeled as “selective” herbicides. These are formulated to kill crabgrass while sparing the surrounding turf. For pre-emergent control, look for herbicides containing active ingredients like prodiamine or dithiophyr, which prevent crabgrass seeds from germinating without affecting establish lawn grasses.

If crabgrass is already present, opt for a post-emergent herbicide with ingredients such as guinclorac or fenoxaprop, which are effective at kill crabgrass without harming most cool- and warm-season grasses. Always check the label to ensure compatibility with your specific grass type, as some herbicides can damage certain varieties, like fescue or Bermuda grass. To ensure your herbicide is its most effective, apply pre-emergents early in the season and post-emergents when the crabgrass is young.

For homeowners looking for the extra mile, you can find additional research on how effective various herbicides are from the Management of Invasive Plants in the Western USA, a project dedicated to the investigation of policies and practices used to limit the spread of invasive plant species.

Proper Application Techniques for Crabgrass Control

Applying herbicides effectively requires careful attention to timing, proper equipment, and precise application to ensure success while minimizing damage to your lawn. For pre-emergent herbicides, timing is crucial. Apply them in early spring, just before soil temperatures reach 55°F, which is when crabgrass seeds begin to germinate. A soil thermometer can help you gauge the right moment. If using a post-emergent herbicide to target existing crabgrass, apply it when the weeds are young and actively growing, typically in late spring or early summer.

To apply herbicides evenly, use a broadcast or drop spreader for granular products, ensuring even coverage without overlapping passes. For liquid herbicides, a handheld or backpack sprayer allows for precise spot treatment of affected areas. Always calibrate your equipment according to the product’s instructions to avoid over- or under-application. Additionally, apply herbicides during calm, dry weather to prevent drift or runoff, and avoid mowing the lawn for a few days before and after application to allow the herbicide to fully absorb.

Post-Treatment Lawn Care

After applying chemical treatments to control crabgrass, proper lawn care is essential to help your grass recover and thrive. First, avoid mowing the lawn for a few days after the treatment to allow the herbicide to fully penetrate the weeds and take effect. After a few days and you’re ready to resume mowing, get an instant quote for LawnGuru’s lawn mowing service and start your journey to a weed free lawn. Watering your lawn lightly a day or two after application can help the herbicide settle into the soil and reach the roots of the crabgrass, but be cautious not to overwater, as this may dilute the treatment. Once the weeds begin to die off, focus on nourishing your lawn with a balanced fertilizer to promote healthy grass growth.

Additionally, regularly aerating the soil can also improve root development and help your lawn absorb nutrients more effectively. Overseeding any bare spots left by the dying crabgrass will help fill in gaps and prevent new weeds from taking hold. By combining these care practices with consistent mowing and proper watering, you can restore your lawn’s health and not have to think about how to get rid of crabgrass again. For homeowners looking for the extra mile, you can find additional research on how effective various her