When Do Leatherjackets Pupate?

Leatherjackets pupate mid- to late spring just below the soil surface. In late summer and fall, adults emerge to start the cycle again.

When should I treat my lawn for a leather jacket?

The Nematodes (or Steinernema Feltiae) should be watered onto the lawn between August and October when the ground temperature is still warm and moist. This is also the time the adult crane flies lay new eggs which hatch and often start feeding on the lawn before going more dormant over Winter.

How long do nematodes take to kill leather jackets?

How Long Does It Take To See Results? Usually 3-7 days, with maximum effect occurring over 2-4 weeks. Nematodes disintegrate the pests from the inside out, so you will not see dead insect bodies as you would with a chemical knockdown.