Seeing thick, star-shaped, wide-bladed grass spreading quickly across your lawn this summer likely indicates crabgrass. This tough weed in Utah can produce up to 150,000 seeds per plant. With the right timing and approach, you can manage crabgrass. Here’s what homeowners in Utah County and Salt Lake County should know.

Before Tackling Crabgrass control, it’s important to know what crabgrass is and how to spot it in Utah lawns. Crabgrass is a warm-season annual weed. It starts growing in spring, spreads quickly through summer, and dies with the first hard frost, but not before dropping thousands of seeds that will sprout the next year. The plant is named for the way its stems spread from a central point, resembling crab legs.

You can spot crabgrass in Utah lawns by looking for wide, flat blades that feel rougher than regular turf grass. The grass is usually light green or yellowish-green, grows low and spreads out, and its stems often root where they touch the soil. In mid to late summer, you’ll also see finger-like seed heads.

Crabgrass grows best in the same conditions found in Utah County and Salt Lake County: full sun, hot weather, compacted or thin grass, and disturbed soil near lawn edges, driveways, and sidewalks. If your lawn has thin or bare spots, crabgrass will take advantage of them.

Crabgrass seeds sprout when soil temperatures are 55–60°F for several days, usually in late April through May. Alkaline soils, strong sun, and dry summers in Utah help crabgrass thrive, especially in new developments with disturbed soil, thin grass, and newly adjusting irrigation systems.

The best way to stop crabgrass is to use a pre-emergent herbicide before the seeds germinate. Pre-emergents form a barrier in the soil that prevents new seeds from germinating. If crabgrass is already visible, pre-emergents won’t work anymore.

In Utah and Salt Lake Counties, apply pre-emergent when soil temperatures reach about 50°F at a 2-inch depth. This usually happens from late March to mid-April in the valley, and a bit later in higher areas. A good rule of thumb is to apply pre-emergent when forsythia shrubs are blooming in your neighborhood.

Choose products that contain prodiamine, dithiopyr, or pendimethalin. These are types of pre-emergent herbicides, meaning they stop weed seeds like crabgrass from sprouting before you see them above ground. After applying, water your lawn with about a quarter to half an inch of water to activate the product. If you miss the first window, you can apply again four to six weeks later to catch any late-sprouting seeds. If you want to make sure it is done right and that you don’t hurt your lawn, check out our weed control services.

If you already see crabgrass in your lawn, use a post-emergent herbicide next. These work best on young, actively growing crabgrass, especially when the plants have fewer than five branches. Treating older plants in late summer doesn’t work as well and might not stop them from producing seeds.

For established Utah lawns, products containing quinclorac, fenoxaprop, or mesotrione (the main ingredient in Tenacity) are often used to control crabgrass. Always read the label carefully, since some products aren’t safe for every type of grass. Tall fescue and Kentucky bluegrass each react differently to certain herbicides. Do not apply post-emergent herbicides when temperatures exceed 85°F, as heat stress on the turf increases the risk of lawn damage. Wait for a cooler window or treat in the early morning. Leave it to the pros and contact us today!

For small patches, hand pulling can work if you do it right. Pull out the whole plant before it produces seeds, making sure to get as much of the root as you can. Wear gloves and throw the pulled plants in the trash, not the compost, since seeds might already be present. Afterward, fill in bare spots with grass seed to prevent crabgrass from returning.

A thick, healthy lawn is your best long-term protection against crabgrass and other weeds. Thin or stressed grass lets crabgrass get the sunlight and open soil it needs to grow. Try these tips to make your lawn denser over time.

Mow cool-season grass to 3–3.5 inches in summer. Saratoga Mowing lawn mowing services are available, and you can schedule with us today. Taller grass shades the soil, helping prevent crabgrass. Fertilize on schedule to keep your lawn healthy and outgrow weeds. Overseed thin spots in late August or early September, and aerate before overseeding.

Watering your lawn often but not deeply helps crabgrass grow and weakens your grass’s roots. Instead, water deeply but less often—one or two deep watering sessions per week, using about one inch of water in total. This helps your lawn’s roots grow deeper and makes your grass more drought-resistant than crabgrass. If you need help checking your sprinkler system and/or setting your timers, we offer sprinkler services.

Late March to mid-May: Apply pre-emergent herbicide when soil temperatures reach 50°F. Late May to June: Watch for early crabgrass and use post-emergent treatments if needed. July to August: Keep spot-treating young crabgrass, but avoid spraying during hot weather. August to September: Overseed thin spots after crabgrass dies and aerate before seeding. October to March: Plan your pre-emergent for next spring and test your soil if needed.

Getting the timing right for pre-emergent applications is the most important—and often the hardest—part of crabgrass control for homeowners. If you miss the window by even two weeks, you could be dealing with crabgrass all summer. At Saratoga Mowing, we offer weed control treatments based on Utah’s real soil temperatures, not a generic national schedule, so your lawn gets the right protection at the right time. We serve Saratoga Springs, Eagle Mountain, Lehi, American Fork, Highland, Pleasant Grove, Orem, Provo, Sandy, South Jordan, West Jordan, Draper, and nearby areas. Don’t wait for crabgrass to take over—call orcontact us today for a free quote and let our experts help you reclaim your lawn.