Homeowners who care for their lawns continually battle crabgrass. Crabgrass can give your lawn an unkempt appearance and can quickly take over if not kept in check, causing a real problems for lawns. The best way to get rid of crabgrass is to be proactive. If you let it take over, your beautiful lawn may quickly turn shabby.
What is Crabgrass?
Crabgrass is a warm season annual weed, so it germinates, lives, and dies all in the same season. Since crabgrass thrives in hot, dry conditions, it flourishes from late spring through the warm summer months, causing thin and bare spots in your lawn.
At the end of the warm season, crabgrass dies with the first frost. While the grass itself dies, its plentiful seeds do not. Those seeds stay behind, ready to germinate the following spring and start the cycle all over again in even higher numbers.
Crabgrass gets its name because it grows low to the ground with stems that radiate out of the center, similar to the legs of a crab.
How to Prevent Crabgrass
Pre-emergent Herbicides
The best way to defeat crabgrass is to use pre-emergent herbicides in the spring before the crabgrass seeds have a chance to sprout. A pre-emergent herbicide must be applied before the crabgrass emerges from the soil. By the time you see the crabgrass, it’s too late. Watch the ground temperature in the spring to time your pre-emergent treatment.
Apply in late February or early March before soil temperatures reach 55 degrees, which usually coincides with forcythia blooming.
This method will prevent crabgrass from ever taking root, and ensure that your lawn stays healthy and free of this pesky weed.
Maintain a Healthy Lawn
In addition to treating your lawn with a pre-emergent herbicide, there are a few lawn maintenance practices that can help keep your lawn crabgrass-free. The healthier your lawn is, the less susceptible it is to crabgrass and other weeds. A thick, healthy lawn will reduce weed growth and make it easier to treat weeds that do sprout.
- Watering Practices
Water the lawn deeply once per week to encourage a deep grass root system, making the entire lawn more hardy and heat tolerant. - Mow High
While some special situations, such as sports fields or golf courses, mandate grass be mowed short, residential lawns can be kept longer. Keeping your grass in the optimal growing range will help shade the soil, making it harder for weeds to get the sunlight they need to grow.
- Use Sharp Mower Blades
Dull mower blades rip the grass, leaving a raw, tattered edge rather than a clean slice. The jagged edges heal more slowly, making the grass more susceptible to disease. - Leave Lawn Clippings as Natural Fertilizer
If you obey the 1/3 rule, never cutting more than one-third of the grass blade length at a time, there is no need to rake and bag the clippings. Let them feed your grass.
- Use Sharp Mower Blades
- Reduce Compaction
Weeds thrive in compacted soil, which deprives grass roots of air and water circulation they need. Aeration loosens compacted soil and exposes the roots to sun, water, and nutrients.
Pro Tip
It is important not to aerate immediately after applying pre-emergent herbicide.
Aerating will disrupt the herbicide barrier and reduce its effectiveness.
How to Get Rid of Crabgrass
Recognize and Remove Crabgrass Early
Carefully pulling out young crabgrass shoots is a surprisingly effective and chemical-free way to control crabgrass. Look for light green grass blades that do not yet have splayed seed heads and remove them as soon as possible.
Fully mature crabgrass will have seed heads that spread out like a fork. If you see crabgrass with splayed seed heads, leave them alone. Mature, splayed seed heads can scatter thousands of seeds all over your lawn.
Treat with Post-emergent Herbicide
If crabgrass has already infested your lawn, chemical treatment may be necessary. While pulling crabgrass by hand is effective, some roots can be deeply embedded in your lawn. Use a post-emergent herbicide specifically labeled for crabgrass. Be sure to carefully read and follow all label instructions and warnings since not all post-emergent herbicides work the same.
Post-emergent herbicides for crabgrass will come in a sprayable liquid form meant for spot treating, not for broadcast application. A selective post-emergent crabgrass killer will remove the weed without killing lawn grasses such as Bermuda, zoysia, fescue and bluegrass.
After the first post-emergent application, be on the lookout for any new crabgrass sprouts and remove them. If new sprouts are too numerous, another herbicide treatment may be required.
Pay Special Attention to Trouble Areas
Areas such as driveways, sidewalks, and curbs tend to absorb a lot of heat during summer months, making them susceptible to crabgrass. Keep a close eye on such areas and diligently remove young sprouts or thoroughly treat these troublesome areas with post-emergent herbicides.
Crabgrass can disrupt your lawn and spoil its appearance. Take control, break the cycle, and prevent crabrass spread.
Have more questions about weed control in your lawn? The Certified Turfgrass Professionals at NG Turf are happy to answer any sod care questions you may have. Give us a call at 770-832-8608 or email info@NGTurf.com.
