Apply chlorantraniliprole (GrubEx) in April or May as preventive

What to Do

Apply Scotts GrubEx (chlorantraniliprole 0.08%) or equivalent between April 1 and May 30 at the label rate. Water in lightly after application. This prevents the next generation of grubs from establishing in summer and fall.

Why It Works

Chlorantraniliprole moves into the soil and is absorbed by grass roots. When newly hatched grubs feed on treated roots in July-August, they die. MSU Extension research shows applications before June are more effective than later ones, achieving 65-80% grub reduction. It is also safe for bees and pollinators — EPA designates it a low-risk pesticide.

Tips

• This is strictly preventive — it will not kill grubs already present in spring.
• Apply any time after the grass greens up, up to mid-July at the latest.
• One application lasts the entire season.