Want to know how to kill crabgrass in your yard for good? It’s all about being proactive because this particular warm-season annual weed is a tough species. Digitaria or crabgrass, is a difficult thing to combat in your lawn. That’s probably not much of a surprise but it’s worth noting just how problematic it is to deal with, year after year.
There are three effective methods for killing crabgrass: using a pre-emergent herbicide, using a post-emergent herbicide, and organic control. The first two are more powerful but all three aren’t exactly predictable. It’s really a matter of experimentation to get the results sought. While this isn’t necessarily a ringing endorsement, it goes to show just how difficult killing crabgrass is to do.
About Digitaria or Crabgrass
Many people wonder why it is so hard to kill crabgrass. Well, digitaria, or crabgrass, is very adept at eluding control. This is because it is a warm-season weed that starts growing as the weather warms. Here in sunny Sarasota, winters are ultra-mild, but grass does still go dormant. Crabgrass is killed off in cold-weather climates during the fall and especially during the winter when frost, snow, and ice conditions appear. And, even though crabgrass isn’t truly drought tolerant, it’s very difficult to get rid of completely.
Crabgrass is a tough opponent, but with a lawn spreader, a pump sprayer and a few turf products you can get rid of crabgrass in the spring and control it throughout the summer. The best weapon you have against this annual weed is crabgrass preemergence herbicide (also called crabgrass preventer). You apply this product in the spring before the crabgrass seed sprouts. This granular herbicide works by creating a chemical barrier at the surface of the soil. As the seeds begin germination, they take in the herbicide and die. —Family Handyman
In a typical cold-climate cycle, crabgrass dies during the fall and winter, but that’s just the plant itself — not the seeds. During mid-summer through fall, digitaria produces its seeds. Then, when the spring soil temperatures reach between 55 and 60 degrees Fahrenheit (at a depth of 2 to 3 inches), those seeds germinate. Viola! Crabgrass now begins to grow freely, wreaking havoc on your beautiful lawn and rudely interrupting your landscaping.
How to Kill Crabgrass in Your Yard for Good
Although crabgrass is tough, it isn’t invulnerable. Because there’s very few times freezing conditions befall us here in west-central Florida, you’ll probably see digitaria just about the entire year. And even though it does go dormant in the fall through the winter, only the plant itself might die off. This however, doesn’t account for its seeds. And that’s where the battle must be fought in order to win. Here are some methods for how to kill crabgrass in your yard for good:
- Use a pre-emergent herbicide. There are several pre-emergent herbicide products available and you should ask your local nursery which are the most effective in killing crabgrass before it has a chance to germinate. Keep in mind that pre-emergent is just that — prior to the seeds germinating, so this a proactive measure. Irrigate after apply the pre-emergent herbicide and reapply the herbicide periodically. Always follow the manufacturer’s instructions and don’t dethatch or aerate after application. Also, don’t use pre-emergent herbicide on new sod.
- Use a post-emergent herbicide. If you already have crabgrass growing in your yard, it’s still possible to kill off. However, this is a more difficult method because you’ll only kill the plant and not the seeds. So, you’ll see digitaria reappear and have to reapply more post-emergent herbicide. The challenge is to spot crabgrass in its infancy. Once crabgrass begins to germinate, you can no longer rely on pre-emergent herbicide and you’ll have to be careful with applying post-emergent herbicide so you don’t harm healthy grass.
- Use organic control. You can also control crabgrass by keeping your yard hardy. Healthy grass is a great partner to weaponize against the weed. You don’t have to use any chemicals but bare in mind, it’s very difficult to kill off otherwise. So, using a combination of pre-emergent herbicide and beefing up your grass is a winning combination to control crabgrass. Simply use a good fertilizer, don’t allow bare spots to linger, water deeply but do so less frequently, and mow high during the summer, leaving grass about 2 1/2 to 3 inches high.