How to Get Rid of Lawn Grubs: Treatment & Prevention
Learn when to treat lawn grubs, which products work best, and how to prevent them. Step-by-step guide to eliminate grub damage before it spreads.
Lawn grubs are beetle larvae that live in your soil and feed on grass roots. If you see brown patches of dead grass that pull up easily, or notice increased mole or bird activity in your yard, you probably have grubs. The good news: you can get rid of them with the right treatment at the right time.
Getting rid of lawn grubs means understanding two different approaches: preventative treatment (stopping grubs before they cause damage) and curative treatment (killing grubs after you spot the damage). Which one you use depends on when you notice the problem and how bad it is.
Preventative Treatment: Stop Grubs Before They Start
The best time for preventative grub treatment is mid-April through mid-June. This is when adult beetles lay eggs in your soil, and the larvae are just starting to hatch and feed.
Related: How to Prepare Your Lawn for Winter: Step-by-Step Guide
Preventative products use ingredients like carbaryl or trichlorfon. These work by killing the young grubs before they get large enough to cause visible damage to your lawn.
The benefit of preventative treatment is that you stop the problem early, when grubs are small and easier to kill. The downside is that if you don't actually have grubs, you're treating for nothing. But if you had grubs last year or you live in an area where they're common, preventative treatment in spring makes sense.
Curative Treatment: Kill Active Grub Infestations
If you already see dead patches or your grass is pulling up easily, you have an active infestation. That's when you need curative treatment.
Curative products are sometimes labeled "24-hour grub killer" and typically contain trichlorfon or carbaryl. These are stronger formulations designed to kill grubs that are already feeding and causing damage. Apply curative treatment as soon as you spot the problem.
The timing matters because grubs are most vulnerable in late summer and early fall (August through October). If you catch them during that window, curative treatments work best. Treating in winter or early spring is less effective because the grubs are deeper in the soil and harder to reach.
How to Apply Grub Killer Safely
Always wear rubber gloves and rubber boots when handling or applying any insecticide, including grub killers. Follow the product label exactly for mixing and application rates.
Most products come as granules or liquids. With granules, you spread them evenly over the affected area and water them in well so they soak into the soil where grubs live. With liquid sprays, you apply them to the grass and soil according to the label instructions.
Water your lawn thoroughly after application. This helps the product reach the grubs in the soil and reduces the risk of the treatment sitting on the surface where it's less effective.
Never exceed the recommended dose, and keep children and pets off the treated area until it dries or until the label says it's safe.
Prevention: Stop Future Infestations
The real secret to avoiding grub problems is removing their food source. Grubs eat grass roots, so a healthy, dense lawn is your best defense.
Keep your lawn properly watered (about 1 to 1.5 inches per week), mow at the right height for your grass type, and avoid over-fertilizing, which can attract beetles. A thick lawn means grubs have less access to soil and fewer roots to eat.
You can also reduce the adult beetle population by keeping outdoor lights off at night during peak beetle season (June and July). Beetles are attracted to lights, so fewer lights mean fewer beetles laying eggs in your yard.
If grub problems are severe or you're not comfortable applying pesticides yourself, a licensed lawn care professional can handle both the diagnosis and treatment.
When to Call a Professional
You don't need a professional just to treat grubs, but you might want one if the infestation is severe (more than half your lawn is damaged), if you've never applied pesticides before, or if you're uncomfortable handling chemicals.
A lawn care professional can identify whether you actually have grubs (sometimes lawn damage comes from other causes), recommend the best treatment, and handle the application for you. They can also give you a plan to prevent future infestations.
Costs for professional grub treatment vary by region, lawn size, and the severity of the infestation. Get estimates from a few licensed professionals in your area to understand your options.
Common questions
Look for patches of brown or dead grass that pull up easily. The soil underneath will feel soft and spongy. If you dig up a small section of dying grass and see white, C-shaped larvae about 1/4 to 1/2 inch long, those are grubs. Increased activity from moles, skunks, or birds digging in your lawn is also a sign, since they're hunting for grubs to eat.
Yes. Fall (August through October) is actually one of the best times to treat active grub infestations with curative products. The grubs are actively feeding and closest to the soil surface, so treatments are most effective. Spring treatment is also possible but usually less effective than fall.
Preventers (applied in spring) kill young grubs before they grow and cause damage. Killers (curative products) target grubs that are already established and actively feeding. You choose based on whether you're treating before or after you see damage.
Curative treatments can work within 24 hours, depending on the product and temperature. Preventative treatments work over a few weeks as grubs hatch and feed. Even after grubs die, your grass may take a few weeks to recover, so be patient.
