No one wants to ruin their lawn in the summertime by having crabgrass plants popping up throughout. Establishing a thick, healthy turf is essential at preventing lawn weeds – both grassy weeds and broadleaf weeds.
But what if you skipped a crabgrass preventer in the spring? You’ll need to control crabgrass and other weeds in the summer… Here are some steps that will help get rid of crabgrass during the summertime.
Table of Contents
How To Control Crabgrass
Weed & Crabgrass Killer
The best post-emergent crabgrass killer herbicides are selective herbicides containing, Quinclorac, Mesotrione, or Fenoxaprop-p-ethyl. These target grassy weeds like lawn crabgrass and can provide some broadleaf weed control. We’ve identified the best crabgrass killer below:
- Active Ingredient: Quinclorac
Syngenta Tenacity Turf Herbicide
- Active Ingredient: Mesotrione
- Active Ingredient: Fenoxaprop-p-ethyl
These are the best and most effective products to kill crabgrass – especially when crabgrass is beyond the 2nd tiller stage. It is important to first know your grass type. Some of these weed killers can also harm, or kill your good grass, too. Here is a table below that shows whether the grass is for labeled use for each product.
| GRASS-TYPE | DRIVE XLR8 | TENACITY | ACCLAIM EXTRA |
| FESCUE | YES * | YES | YES |
| KENTUCKY BLUEGRASS | YES | YES | YES |
| PERENNIAL RYEGRASS | YES | YES | YES |
| ST. AUGUSTINE | NO | YES | NO |
| ZOYSIA | YES | NO ** | YES |
| BERMUDAGRASS | YES | NO *** | YES |
| CENTIPEDE | NO | YES | NO |
| BUFFALOGRASS | YES | YES | NO |
| BAHIAGRASS | NO | NO | NO |
- * Fine Fescue if seed blended
- ** If grown from sod
- *** Apply on domant grass only
Weed & Crabgrass Preventer
Crabgrass will emerge in the spring from seeds as soil temperatures reach 55 degrees, and grow and thrive in the hot summer months. Crabgrass dies in the fall after it has dropped its seeds, and the lifecycle starts all over again the following spring. That’s why it is critical to prevent weeds before they germinate and get established in your lawn. Apply a split application of pre-emergent herbicide in preventing crabgrass.
Early spring: A product containing Prodiamine. Can be 0-0-7 or a combo with lawn fertilizer like 19-0-7
Early summer: A second application containing Dimension (Dithyopyr) – a combination containing lawn fertilizer is an effective option.
Corn gluten meal can be used for organic lawn care but can take a couple of years of consistent applications to become effective.
For more details, check out our post on when to apply crabgrass preventer.
Weed Removal Tool
There are a number of crabgrass removal tools on the market. These are good to have to incorporate an Integrated Pest Management (IPM) program – particularly for lawns that see the occasional single crabgrass plant.
Lawn Fertilizer
The key to a weed-free lawn is by building a thick, healthy turf. This requires mowing your lawn regularly, proper watering, and of course regular fertilizer feeding. We don’t recommend using a weed and feed product, but rather using fertilizer and broad-spectrum herbicide separately.
Other Herbicides
Other broad-spectrum herbicides can be used but, again, it is important to read the labels for the “weed species controlled” and “for use in turfgrass species”.
Non-selective weed killers such as glyphosate (RoundUp) kills weeds, but it also kills lawn grasses and everything else it comes in contact with. The same can be said for organic options like vinegar-based solutions like Green Gobbler.
What kills crabgrass in summer?
The best herbicide to kill crabgrass in summer is quinclorac. We recommend Drive XLR8 and methylated seed oil (MSO) for killing crabgrass. Crabgrass thrives in the summer so it is important to prevent crabgrass by killing existing crabgrass plants. Even just a few crabgrass plants can shed thousands of seeds. Over winter, these dormant crabgrass seeds wait until the spring to germinate and emerge as soil temperatures warm up – around 55 degrees consistently for 3-4 days.
Can I treat crabgrass in the summer?
Yes. The best way to treat crabgrass in the summer, early, is by applying a second application of pre-emergent herbicide, Dimension (Dithyopyr). This will prevent new crabgrass seeds from emerging into new crabgrass plants. For post-emergent control, kill crabgrass in the summer with an herbicide containing Quinclorac.
How do you get rid of crabgrass permanently?
For best crabgrass control, apply a split application of crabgrass preventer: the first in the early spring before soil temperatures reach 55 degrees, and a second as the soil temperatures approach 65 degrees. Crabgrass preventers form a vapor barrier in the soil which prevents crabgrass seeds from emerging. They are coined as root pruning herbicides or root clubbers.
What kills crabgrass and not the lawn?
You will first need to know your grassy type. Next, check the labels of each herbicide to ensure it is safe for your lawn. Quinclorac, Mesortione, and Fenoxaprop-p-ethyl provide great crabgrass seeds control and also kill other grassy weeds, but may harm your turf; particularly some warm-season grasses.
Grassy Weeds vs. Broadleaf Weeds
Grassy weeds like crabgrass are typically annual weeds, which means they drop seeds and die every year. Their seeds stay in the soil over winter and germinate the following year, starting the lifecycle again. These weeds can often be controlled by a pre-emergent herbicide.
Broadleaf weeds are usually either biennial (drop seeds like grassy weeds but live for 2 years) or perennial (have established roots that survive every year). Many broadleaf weeds cannot be controlled by a weed preventer, and need to be controlled and killed post emergently.
