Grubs are beetle larvae that live in the soil. The larvae feed on root systems of plants and, by doing so, often kill the plants. If that isn't bad enough, the presence of a large number of grubs in your yard will attract animals that eat the grubs, such as moles, which also cause damage in your lawn and garden. It is best to detect and eradicate grub worms as soon as possible.
Dig into the edge of your vegetable garden with a shovel and remove one-fourth of a square foot of soil.
Sift through the soil and see if you can find more than four or five grubs.
Move to the center of your garden, remove another one-fourth of soil with a shovel and examine the soil in the same way.
Look for unusual brown patches in your lawn. Use the shovel to cut through the turf. Lift the grass and soil with your shovel to see if it breaks apart easily.
Try to roll the section of grass like a carpet. It will roll if grubs have eaten the roots.
Purchase an insecticide than contains either imidacloprid or halofenozide.
Apply the insecticide to your garden in July or August to kill all of the immature grubs.
Spread the insecticide in areas of your lawn surrounding the vegetable garden to prevent more grubs from making their way to your plants.
Kill the mature grubs the following spring. Mix Heterorhabditis nematode paste with water and pour the mixture into a sprayer. Spray the garden area with the mixture as directed on the package.