White grubs pose a serious threat to your lawn. These beetle larvae (including June beetles, Japanese beetles, and European chafers) measure about 1.25 cm (0.5 in) and feature a characteristic C-shaped white body. By devouring your lawn's root system, they cut off access to water and nutrients, causing the grass to die off in patches. Fortunately, concrete solutions exist to take back control of your yard!
Signs of Infestation: How to Spot Them
Inspect your lawn regularly. You must act quickly if you notice:
- Irregularly shaped brown or yellowing patches.
- Dead sections of turf that lift up easily, like a rolled-up piece of carpet.
- Holes dug by skunks, raccoons, or birds turning over the soil to feast on the larvae.
To confirm your suspicions, lift a one-square-foot section of turf. If you count more than 5 to 10 white grubs, the infestation requires immediate intervention.
Prevention: Your Best Defence
A dense, vigorous lawn naturally discourages destructive pests. Adopt these excellent cultural practices to fortify your turf:
- Maintain a good mowing height: Adjust your mower between 8 and 10 cm. Taller grass blades shade the soil, protect the roots from drought, and prevent beetles from reaching the earth to lay their eggs.
- Fertilize properly: Nourish your lawn with a balanced formula to thicken the root system.
- Water deeply: Prioritize less frequent but longer watering sessions. This method forces roots to anchor themselves deeply into the soil.
Scotts® Grub B Gon MAX® Grub Killer: Your Effective Ally
Since the restrictions on certain chemical pesticides in Quebec, gardeners have been seeking powerful alternatives. Scotts® Grub B Gon MAX® Grub Killer meets this need perfectly. Its active ingredient, Bacillus thuringiensis subsp. galleriae (Btg), is a naturally occurring live organism that effectively controls a wide variety of beetle larvae through ingestion, while remaining environmentally responsible for your garden.
The Treatment Calendar: When and How to Act
To maximize the impact of Scotts® Grub B Gon MAX® Grub Killer, synchronize your applications with the life cycle of the white grubs:
- Spring (April–May): Larves that overwintered beneath the lawn move up to the surface to feed as soon as the ground thaws. Mid-April represents the ideal time to apply the product to eliminate these grubs before they metamorphose into flying adults. For optimal performance, ensure the soil temperature reaches a consistent minimum of 15°C, allowing the active bacteria to deploy fully.
- Mid-Summer (July–August): Adults lay their eggs in July, and they hatch around late July or early August. This is the perfect time to act: apply the treatment in late July or during August when the soil is warm. At this specific stage of development, the larvae are tiny, highly voracious, and stay near the surface to gnaw on roots, making them extremely vulnerable to the product.
- Autumn (September): Larvae continue to feed voraciously before the cold sets in. An application in mid-September works well to decimate the colony, protecting your lawn before winter and drastically reducing the impact of grubs the following spring. Apply the treatment before the soil cools below 15°C and the larvae burrow deep down to hibernate.
How to Apply the Product
Application is simple using a broadcast or rotary spreader. For optimal results, mow your lawn before treatment and distribute the granules onto dry foliage.
The Golden Rule for Success: You must apply the product to a soil that is already moist. Furthermore, a generous watering (about 1.5 cm of water) immediately after application is essential to activate the bacteria and wash it directly into the root zone where the grubs hide. Never skip this step! Always consult the product label to adjust your spreader settings.
Storage Advice: Store the product in a cool place between 4°C and 25°C, and use it within 17 months of the manufacturing date. *This treatment controls a broad spectrum of pests: annual bluegrass weevil, Asiatic garden beetle, black turfgrass ataenius, European chafer, green June beetle, Japanese beetle, May or June beetle, Northern masked chafer, Oriental beetle, and Southern masked chafer.
