IPM Focus: Nematodes

Now is the best time to apply nematodes for control of many soil-dwelling pests

The larval stages of several soil-dwelling pests including vine weevil, chafer grubs, wireworms, leatherjackets and others can cause considerable damage to plant roots and tubers resulting in decreased plant vigour, crop damage, plant death, and if the pests are allowed to mature to the adult stage in large populations will cause further extensive crop damage. Targeting with nematodes at the correct life stage is key to effectively controlling populations and keeping your plants safe from these hidden pests.

Kept in suspension within water and applied to the soil using a watering can, knapsack sprayer or irrigation system (remove filters) nematodes will target soil-dwelling pests by entering the host through natural openings. Within the host the nematode releases a specialist bacteria that takes over and kills the infected host. Once matured the nematodes leave the original organism and search for further soil pests to parasitise.  

Late Summer/ early Autumn presents the optimum time to target soil-dwelling pests whilst the soil is mild, they are present within the shallow topsoil prior to entering diapause during the winter months where they burrow deeper into the soil. Targeting early on in the pest’s lifecycle will result in reduced plant damage due to a shortened feeding period for the pest.  

Depending on climatic temperatures and pest species, Fargro offers a variety of nematode species that seek out soil-dwelling pest species:

Exhibitline Hb Heterorhabditis bacteriophora 
  • Vine Weevil, Garden Chafer, wireworm
  • Apply when soil temperatures are above 12°C.
  • Maximum soil temp 28°C.


Nemasys L Steinernema kraussei 
  • Vine Weevil, Chafer grubs
  • Apply when soil temperatures are above 5°C.
  • Maximum soil temp 30°C.

Exhibitline Sf Steinernema feltiae
  • Carrot & Cabbage root fly, Sciarid Fly, Thrips, Leafminer, Leatherjackets
  • Apply when soil temperatures above 10°C.
  • Maximum soil temp 30°C.

Exhibitline Sc Steinernema carpocapsae
  • Leatherjackets, Cutworms most caterpillar species including codling moth larvae & sawfly larvae
  • Apply when soil temperatures are above 12°C.
  • Maximum soil temp 26°C.

To place an order of for more advice, please contact our Technical Team on 01903 256857 or email biosales@fargro.co.uk.