What will kill grub worms?
There are many natural treatments
Milky spore , the spores are applied to affected lawn areas, infecting lawn grubs as they feed. Once the grubs die and decompose, additional spores are released into the soil, which helps prevent further infestations.
Neem oil is a botanical pesticide containing insecticidal properties. Neem oil works more as a repellant, inhibiting egg laying, growth and feeding. Neem oil is mixed with water (as directed) and sprayed onto affected lawn areas.
Beneficial nematodes are also used as natural grub treatment. These tiny, soil-dwelling worms release bacteria into the soil that infects and kills lawn grubs. Nematodes are available in liquid form or mixed with water and sprayed onto affected areas.
Read more at Gardening Know How: Lawn Grubs – How To Get Rid Of Grub Worms https://www.gardeningknowhow.com/plant-problems/pests/insects/get-rid-of-grub-worms.htm
