Nemasys Leatherjacket Killer (Spring 250sq.m)


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What are Leatherjackets?

Leatherjackets are the larval stage of the crane fly or daddy-long-legs, they are are about 2.5cm (1" long), greyish black in colour, legless and with no distinct head (see pictures above).


How can I control Letherjacket larvae?

Use Nemasys Leatherjacket Killer to deal with a leatherjacket infestation, without any of the precautions associated with harmful chemicals.

Nemasys Leatherjacket Killer is incredibly effective and is 100% safe for children, cats, dogs, other pets and wildlife. 


When can I apply Leatherjacket Killer Nematodes?

  • Autumn application - typically late August through to the end of October:

When you start to see the adult daddy-long-legs in your garden (towards the end of August) you will know that in a few days they will be laying eggs. These will hatch quickly; therefore aim to apply two weeks after you see the adults.

This is when the young leatherjackets are active in the soil and is when they are most susceptible to the nematodes.

  • Spring application - typically April to June:

If you have discovered Leatherjackets (not daddy long legs) at any other time of year i.e. in the spring/summer then treat at double strength as the mature LeatherJackets are much harder to kill -  you must treat in autumn as well.


Where a severe LeatherJacket infestation is present, multiple treatments over an extended period (spring and autumn) may be required.


How do Leatherjacket Killer Nematodes work?

The nematodes (Steinernema feltiae), seek out the leatherjackets and attack the pest by entering natural body openings. Once inside, they release bacteria that stops the pest from feeding, quickly killing the pest.

The nematodes then reproduce inside the dead pest and release a new generation of hungry infective nematodes, which disperse and search for further prey.


How do I apply LeatherJacket nematodes?

Apply the nematodes to moist lawns when the soil temperature is above 10ºC (50ºF). Immediately after application water the grass well so the nematodes are washed into the soil to reach the roots where the leatherjackets will be and make sure the lawn does not dry out after applying nematodes.

Applying Nematodes with a hose end feeder:

  1. Divide the 250 sqm to be treated into 50 sqm areas.
  2. Wash the feeder through with water to ensure it is clean.
  3. Divide the pack into 5 equal portions.
  4. Add 1 portion i.e. a fifth of the pack to feeder bowl. Then fill the bowl with water before attaching the hose.
  5. Taking care to keep the feeder in an upright position apply evenly to 100 sqm for 8 minutes using a side-to-side motion to keep the nematodes well mixed. During this time most of the nematodes will have been applied.
  6. Treat the same 50 sqm area again for a further 16 minutes to apply the remaining nematodes as well as to make sure they are adequately watered in.
  7. Repeat the procedure with the other 4 portions treating each 50 sqm area.
  8. Adhering strictly to the application timings will ensure that any remaining colour in the bowl will be due to inert carrier only and that you have performed an even application.
  9. Make sure the lawn does not dry out after applying nematodes and keep it well watered for at least two weeks. THIS IS VERY IMPORTANT!


Which pack size do I need?

To calculate your area measure the width and length of the area to be treated and multiply them by each other e.g. 10m x 25m = 250 sq.m


Leatherjacket Killer - Spring application must be made at double strength - therefore this pack treats 250 sq.m - even though the outer sleeve shows 500 sq.m.

Can't see an answer to your question? Please contact us and we will be happy to assist you.

Customer Reviews

Nemasys Leatherjacket Killer (Spring 250sq.m) rated 4.8 out of 5 based on 14 reviews.