Grub control and prevention is critical to a quality lawn care program. Part of that program is choosing the right product for grub control. More important than the right product is the time of year each grub product is applied. The chemicals and active ingredients of different products have different effects and residual implications.
Grub control products that contain Chlorantraniliprole, such as Acelepryn and GrubEx, must be applied in early spring, around early May. However, Imidacloprid products, such as Merit, are best applied in the early summer, like the middle of June. It is important to understand that grub control products are not the same as grub killers.
Grub control will not control or kill grubs larvae that are active in the early fall but prevent the grub damage. Adult beetles lay eggs and the grubs hatch during the summer. Damage to lawns occurs through the summer and fall, specifically July through September.
Continue reading to find out more about the best grub control products and best grub prevention.
Best Grub Control Products
Acelepryn G Insecticide by Syngenta is the best product on the market, with the active ingredient being Chlorantraniliprole. This is an incredibly effective chemical in preventing and controlling white grubs, armyworms, and other lawn pests. It is the same main ingredient as Scott’s GrubEx. Acelepryn has a higher concentration of the chemical making it much more superior for prevention. This also makes it slightly more expensive.
It has a low level of toxicity. It comes in liquid and granular options. I used the liquid grub killer this season and had zero lawn grubs. Meanwhile, I used Merit the previous and had two sections of grub damage. I highly recommend spending the money to rest assured that lawn grubs are prevented and under control.
After a 2020 lawn care season (using Merit) with two sections of grub activity and damage, I opted for Acelepryn liquid in 2021 for me and my clients and all had zero grub damage. This is the #1 product hands down.
- Does not have a bad odor
- Large application window allowing you some flexibility for application
- Do not spray on fruits and vegetable gardens
25 pound bag:
- Application rates: 1.15 – 2.3 lbs. per 1,000 sq ft
- Coverage: 10,800 – 21,700 sq. ft.
- Timing: Early May (spring)
- Notes: Water in immediately after application or allow rainfall to move the product into the soil
- Chemical class: Anthranilic Diamide
Now also available in 64 oz. and NEW 4 oz. liquids!
2. Milky Spore
The Milky Spore is the number one grub control product for organic lawn care. Milky Spore is not only safe but effective to control grubs. Milky Spore must be applied three times a year for two years. To create a long-term residual, you can place the granular grub killers in a drop spreader to apply in three seasons (spring, summer, and fall). Milky Spore powder is an organic grub killer that contains a disease bacteria that is able to kill grubs in a way that is safe for the environment.
- Once established, it will last as long as 20 years
- Safe for fish, birds, and fish
- Requires several applications over a period of two years
One of the other options for grub control and grub prevention is Meridian 0.33 G Insecticide. Syngenta makes Meridian and has the active ingredient Thiamethoxam. This broad-spectrum insecticide targets the Japanese beetle, June bugs, Sod webworms, and much more. Meridian is a Group 4A insecticide that provides systemic control of white grubs throughout the growing season. It is recommended that you apply Meridian about 45 days before peak season because that is when lawn grubs are actively feeding on grass roots.
Meridian is a Group 4A Insecticide and provides great systemic control of white grubs throughout the growing season.
Apply up to 45 days before peak season when grubs are actively feeding on grass roots.
- It has little to no smell
- It metabolizes slowly providing season long grub control
- Must water thoroughly after applying
40 pound bag:
- Application rates: 7-9 lbs. per 5,000 sq ft
- Coverage: 22,000 – 28,500 sq. ft.
- Timing: Early May (spring)
- Notes: Water in thoroughly after application
- Chemical class: Neonicotinoid
4. Merit 0.5 G
The next best grub control option is Merit 0.5 G made by Bayer. It has the active ingredient imidacloprid. Merit must be applied early to the middle of June because it does not have the residual activity that Thiamethoxam or Chlorantraniliprole has. Imidacloprid is a neonicotinoid which means it could be harmful to bees. It can systemically control grubs, chinch bugs, Japanese beetles, European Chafers, and other insects in landscape and turfgrass.
Two things to be mindful of with imidacloprid. The first is insecticide resistance. This product should be applied in early to mid-June as it does not have the same residual activity or efficacy as Thiamethoxam or Chlorantraniliprole. The second is that imidacloprid is a neonicotinoid and may be harmful to bees.
Nonetheless, Merit provides good systemic control of Cinch bugs, European Chafers, Japanese beetles, scarab beetles, and more in turfgrass and landscape ornamentals. I’ve used the liquid version with great success against termites, too.
- This is one of most the popular options
- Liquid version works well for termites
- There is breakthrough with this product which means grubs have become resistant
- It is toxic to bees
30 pound bag:
- Application rates: 1.4 – 1.8 lbs. per 1,000 sq ft
- Coverage: 16,000 – 21,400 sq. ft.
- Timing: Mid June (late spring/early summer)
- Notes: Water thoroughly within 24 hours of application. Avoid runoff
- Chemical class: Neonicotinoid
Arena can be used for both grub control and killing grubs. It can be used as a preventative application during the peak time when target species adults lay eggs. The application should be made 60 days or more before the peak adult flight. When it is used as a treatment application, it is used after the eggs hatch. It can also be used once you see the damage to turf.
- Can be used on a wide range of pests including black vine, white grubs, and cutworms
- The area must be completely irrigated after application
GrubEx is made by Scotts and is an improved formula over previous formulas that prevent and kill specific types of grubs (from Imidacloprid to Chlorantraniliprole). It has 25 percent more killing power. This prevents them from damaging your lawn all season long. It has an active ingredient Chlorantraniliprole, but a lower concentration than Acelepryn. It has the ability to kill white grubs, green June beetles, and more.
- Most popular to control grubs
- Easy to find at the local hardware store
- Requires only one application
- Only can be used to prevent grubs from hatching, not controlling mature grubs
FAQs aAbout Grub Control Products
What is the best grub preventer?
Without a doubt, the best grub control and grub prevention is Acelepryn G Insecticide by Syngenta. It has the active ingredient Chlorantraniliprole. This grub killer is effective at controlling and preventing white grubs, armyworms, and many more pests. This will help resolve your grub problem.
What is the best time to treat for grubs?
The best time to treat grubs depends on the product you are using as well as the grub infestation you are facing. Using Acelepryn/Chlorantraniliprole for a grub infestation, you want to use it in early May. When using Merit/Imidacloprid, it is best to apply it in June. If you miss the time to apply the grub control, you may notice active grub infestations and will need a product that kills and gets rid of grubs. You will need the best grub killer to kill grub worms that cause the most damage at the end of summer, between July and September.
When should I apply grub control products?
In the spring. Depending on which product you choose will dictate exactly when you need to apply. Grub insecticides containing Chlorantraniliprole or Thiamethoxam should be applied in early May, while imidacloprid (Merit) should be applied in mid-June as it has less residual activity and efficacy as the other two chemicals.
What is Merit grub control?
Merit is a product made by Bayer. It contains the active ingredient imidacloprid which provides systemic control of many insects including white grub larvae, scarab beetles, Japanese beetles, and more.
White Grub Worm Life Cycle
The life cycle of grubs (often called grub worms) begin when the previous year’s grub worms emerge as June bugs (Japanese beetles) in the spring – between May and June. These adult beetles won’t harm turfgrass but they will feed on and damage trees and ornamentals.
June bugs and adult Japanese beetles will then soon lay their eggs in healthy lawns. Those eggs hatch into white grub larvae in the summer, and it’s those grubs that will damage your lawn throughout the summer and fall months. July through September are when rubs feeding
As the winter rolls around and the soil begins to freeze, the surviving grub worms will bury themselves deeper into the soil before and sleep in a vegetative state overwinter. Once the spring rolls around the following year, grubs will emerge from the soil and become beetles in May/June. And thus the continuous life cycle of the June bug beetles and white grubs.
As they feed on the grass roots throughout the summer and autumn months, you will find irregular patterns of dead brown patches throughout your lawn. You will be able to peel the grass back like a carpet or doormat, and the grubs are usually found along the edges of the damaged turf.