About this product
Leatherjackets are the larvae of the crane fly, and they feed on grass roots through autumn and winter. The damage shows up as yellowing patches that lift away from the soil because there is nothing left holding them down, usually followed by birds and badgers tearing the turf apart to get at the grubs underneath. The secondary damage is often worse than the grubs themselves.
These are Steinernema feltiae, a microscopic beneficial nematode that seeks out the larvae in the soil, enters them and kills them from the inside. Nothing else in the lawn is affected. It is harmless to people, pets, birds, worms and every beneficial insect in the garden, and the lawn can be walked on straight after treatment.
Two things govern whether this works. The soil must be above 10°C, which rules out treating too late in the year, and the timing matters: late summer is the window, while the larvae are still small and near the surface. Treat a mature population in mid-winter and you will be disappointed.
Water the lawn thoroughly before applying, water the nematodes in with a can or hose, and keep the ground moist for a fortnight afterwards. Nematodes move through films of water in the soil, and dry ground kills them within hours. That single point accounts for most treatment failures.
Available in two sizes. This is a live, perishable product. Order by 10am on Monday for despatch later the same week, and apply as soon as it arrives.