Brassica Collars Offer A Simple Solution To Stop Cabbage Root Fly, A Pest That Can Cause Serious Damage To Your Brassica Crops Including Broccoli, Cabbages, Cauliflowers, Calabrese And Brussels Sprouts.stop Cabbage Root Flies Laying Eggs By Placing Collars Over The Base Of Your Young Plants.  this Barrier Method Often Proves More Effective Than Chemicals. 

Keeps Plants Free From Larvae!vine Weevil Have Become More Prevalent In Recent Years And Can Devastate Expensive Container Plants.vine Weevil Larvae Are The Real Problem, Attacking Plant Root Systems From Late Summer Until The Following Spring. The Larvae Over-winter - Attack The Roots - Then Emerge As Adults In Late Spring / Summer. Adults Lay Eggs In The Root-balls Of Plants - Which Then Hatch And Feed Before Repeating The Whole Process Again.by Using Nemasys Twice A Year - In The Spring And Again In Autumn (to Control Larvae Resulting From Eggs Laid In The Summer) You Can Maintain Healthy Plants Free From The Damaging Larvae. please Note: The Ground Temperature Needs To Be Above 5 Degrees For The Predatory Nematodes To Be Active.when You Receive Your Pack Of Nemasys, Place It In The Refrigerator Immediately And Use Within The Use By Date (which Can Be Up To Four Weeks).