I have had to pick the grubs out of the lawn and feed them to the birds up until now! These nematodes are brilliant. Mr G from Essex.
Dear all, I applied your treatment for leather jackets in the autumn and the result, a lawn that looks like a lawn! thanks. Regards Trevor Godwin

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Green Gardener - the natural way to keep your garden looking good
Nemasys Leatherjacket Killer - Leatherjackets are the larval stage of the crane fly / daddy long legs & they can quickly devastate a lawn. They lay their eggs into the same piece of lawn each year, so an infestation can quickly escalate from a small brown patch to a full scale infesation. Birds pecking at the lawn is another sure sign of an infestation. Control Leatherjackets NATURALLY with Nemasys Leatherjacket Killer.


To control Leatherjackets NATURALLY, treat with Nemasys Leatherjacket Killer, which is effective at killing leatherjackets, but is harmless to children, wildlife & pets.


"The nematodes you advised for leather jackets on the lawn last year was very effective, Thank you." K Iris Millar

Nemasys Leatherjacket Killer

Nemasys® Leatherjacket Killer - Leatherjackets are the larval stage of the crane fly or daddy long legs and they can quickly devastate a lawn. Control leatherjackets naturally by treating with Nemasys® Leatherjacket Killer when they are discovered (and the soil temp is 10c) or apply as a preventative measure, by treating when the leatherjackets are at their most destructive i.e. April and/or Sept/Oct. Finished for 2014 - available again in 2015.

Crane flies or daddy long legs lay their eggs in the same area of lawn from which they emerge, so numbers increase rapidly. These eggs hatch in August / Sept and the larvae immediately start to feed on the grass roots. The leatherjackets will feed though the autumn, before overwintering. They start feeding again the following spring and gorge on grass roots before pupating to emerge as adults in August. The symptoms of an attack are that grass growth slows and yellow patches appear PLUS the grass easily pulled up with little or no root growth. One of the biggest indicators of an infestation are birds, particularly starlings, which will pull at the lawn (causing even more damage) in search of the leatherjackets to eat.


Leatherjackets - In August, customers report clouds of daddy long legs emerging from lawns in early morning leaving behind the casings sticking up in the lawn (see left). As the daddy long legs emerge, they start to lay their eggs back in infected lawns starting the whole cycle again - the next generation of leatherjackets hatch within 2 weeks. Leatherjackets are 2.5cm / 1" long, greyish black in colour, legless and with no distinct head.


Treating with Nemasys® Leatherjacket Killer - Control leatherjackets naturally by applying Nemasys® Leatherjacket Killer containing millions of nematodes (Steinernema Feltiae) to the infected lawn in April and or September/October. Nemasys® Leatherjacket Killer is effective at killing leatherjackets, but is harmless to children, wildlife and pets and the lawn may be used immediately after application. Finished for 2014 - available again in 2015.


Nemasys® Leatherjacket Killer should be applied to a moist lawn (we recommend pre - watering) on a dull day or in the evening. After application you MUST wash the nematodes into the lawn by watering heavily with a hose or a sprinkler. To apply, simply mix the nematodes with water and apply large packs with a watering can or hose-end feeder and Economy packs MUST be applied with a sprayer. Once applied the nematodes will seek out the leatherjacket larvae. On contact they enter the larvae and destroy it. Having destroyed the leatherjacket ,the nematodes multiply and are released back into the soil to hunt down more leatherjackets. Nemasys® Leatherjacket Killer is a living, perishable product. Once you receive it, it will keep for up to 2 weeks in the FRIDGE and you must use before the expiry date. Nemasys® Leatherjacket Killer is available in 2 pack sizes, so for smaller lawns just make solution stronger - you can't overdose!


Nemasys® Leatherjacket Killer Large Pack treats 100 sq.m - £19.95

Nemasys® Leatherjacket Killer Economy Pack treats 500 sq.m - £75.00 saving £24.75


"Hi Jon, I keep on forgetting to drop you a line, but I wanted to tell you how good that leatherjacket treatment was. My grass is looking lush again. A bit more rain in recent weeks has helped as well but it is green with no starlings attacking it any more!" Cheers Simon

"The leatherjacket treatment which I got from you for the lawn previously was a great success - thanks!" from K Iris Millar by email


"Dear all, I applied your treatment for leather jackets in the autumn and the result, a lawn that looks like a lawn! thanks" Regards Trevor Godwin


"Hello Jon, this is just to let you know how pleased we are with the leatherjacket control. We applied the nematodes according to the instructions and the brown patches on our lawns have definitely stopped spreading. The fresh grass is already growing. We also used your autumn lawn feed and the benefit is apparent. Last year we helplessly watched as our lawns were mutilated. This year we have been able to fight back. Thank you, from two keen gardeners." Brenda and Cyril.


"Just to let you know we now have a green lawn again – so thank you!" Kind regards Philip 


"Dear Jon, I have 2 lawns but every summer they went mostly patchy yellow and looked half dead and straw like, despite using fertiliser and watering in dry spells. No one could help and then we came across your site and read about leatherjackets. I decided to try your nematodes. I admit I thought it all was a lot of nonsense!! How wrong I was. To my amazement this year both lawns are lush and beautifully green - I find it hard to believe ! Thank you for lovely grass again. I feel that your nematode treatment should be more widely known and written about by gardening column writers to say nothing of books." Many thanks again Derek Wallace

"Thanks for your speedy answer to my questions about the Leatherjacket killer. It is a great product that certainly saved my increasingly ravaged lawn, this year it looked better than it had in ages." Regards Tony



Nemasys® Leatherjacket Killer application methods Nemasys® Leatherjacket Killer is easy to use. Simply mix the harmless powder with water & apply directly to the lawn with a watering can, hose-end feeder or sprayer. Use the whole pack before the expiry date, which is marked on the inside of the pack and will be at least a couple of weeks. Large Packs can be applied with a watering can or Hoseend Feeder, but ECONONY PACKS MUST BE APPLIED WITH A SPRAYER.

  • Haws Rose no.7 Rose - Watering cans need to be fitted with a coarse rose. We recommend using the Haws Rose no.7, as not all roses are suitable.


  • Hose-end feeder - Used for applying large packs of nematodes. This feeder can also be used for applying liquid feed to plants and lawns. Attaches via standard hose-pipe connector and features both a rose head and jet spray as well as an on / off switch for water flow.


  • 5 Litre Sprayer - You must use a sprayer for the application of ECONOMY packs of nematodes and this 5 litre sprayer is ideal. As well as applying leatherjacket and chafer grub nematodes to lawns this sprayer is ideal for other big spraying jobs such as winter wash on fruit trees. This sprayer is easy to use - it features an ergonomic handle, fibreglass lance and an adjustable nossle. A shoulder strap is included, so that the sprayer can be carried making large jobs much easier. Currently unavailable
Large Leatherjacket Killer treats 100 sqm - available again in 2015
Economy Leatherjacket Killer treats 500 sqm - available again in 2015
Haws Rose no.7£4.99Add Haws Rose no.7      
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Hose-end Feeder£12.75Add Hose-end Feeder      
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5 Litre Sprayer - Currently unavailable