The problem – What are Leatherjackets? You may have noticed in the late summer very long-legged insects flying in your garden or house. These are harmless adult crane flies or daddy-long legs which live for only a few days. During that time, they mate and lay eggs in the lawn. These eggs hatch in the early autumn producing leatherjackets which feed on grass roots growing quickly. They are dark brown about 1cm long with NO LEGS and live in the top 5-10cms of soil. (Chafer grubs are the other main lawn pest, but these are white with legs looking rather like a small prawn and subject of another blog). Correct identification of the pest is essential so the right treatment can be applied.

• Leatherjackets are brown/grey torpedo shaped with no visible head or legs.
• Birds such as starlings will peck at the lawn to uncover the grubs to eat.
• The grass will yellow and can easily pulled up with few roots. As the number of leatherjackets increases, the lawn will die off.
• Place a plastic sheet such as a binbag on the affected area and leave weighted down overnight – the leatherjackets will come to the surface and be visible in the morning.

The solution – Nemasys Leatherjacket Killer contains millions of microscopic nematodes each of which contain bacteria. Once applied to the soil, the nematodes seek out leatherjackets to infect. Once infected, the bacteria is released inside the leatherjacket that the nematode feeds on, but this bacteria causes the leatherjacket to curl up and die and in doing so millions more nematodes are released into the soil to keep the process going. Nemasys Leatherjacket Killer will go on working in the soil through the autumn until the soil temperature drops below 10C

• The nematodes occur NATURALLY in the soil, but in very small numbers.
• Apply Nemasys Leatherjacket Killer to boost the number of nematodes to control leatherjackets.
• No other wildlife is affected- even birds eating infected leatherjackets are safe.
• It is safe for you, children and pets.
• The lawn may be used after application and the fertiliser, weed/moss killer applied as normal. The nematodes will not be affected.

When to apply – The best time to apply is in the autumn i.e. Sept / Oct when the leatherjacket eggs have just hatched, the soil is moist and warm i.e. temperature over 10C. Applications can continue until soil temperatures drops below 10C normally in November. It is possible to apply at other times of the year i.e. in the spring and summer provided that the soil temperature is over 10C and the soil is moist, but control is more difficult as the leatherjackets are much older and have a tough protective coat from which they get their name. It is much harder for the nematodes to infect the leatherjackets, so the nematodes must be applied at double strength to make them effective i.e. the normal 100sqm pack will treating 50 sqm when treating in the spring and summer. PLUS, the treatment MUST be repeated in the autumn. N.B. occasionally leatherjackets can be a problem in borders – treat exactly as above.

How to apply – Nemasys Leatherjacket Killer is supplied as a powder in packs treating 100 or 500 sqm. The packs have a shelf life of approx 2 weeks and should be stored in the fridge and then the whole pack should be used in one go. To apply, mix with water and apply to the lawn.

• For small areas use a watering can fitted with a Coarse Rose.
• For larger areas up to 200 sqm use a EasyNem Applicator.
• For the largest areas i.e. over 200 sqm use a specialist Nematode Applicator.

The nematodes need to reach to soil to be effective, so wash them off the grass into the soil with water. Best to apply in the evening, so the grass stays wet longer or apply in the rain if you can!

Reviving a damaged lawn – Once you have the leatherjackets are under control, you can turn your attention to reviving the lawn. The leatherjackets damage the roots, so it is important to feed the roots of the grass to help the remaining grass to recover.

• Apply liquid Root Success Mycorrhizal Fungi  to encourage healthy roots. Leatherjackets attack grass roots, so strengthening the root system is the best way of reviving the lawn. Root Success contains friendly Mycorrhizal Fungi and beneficial bacteria. These fungi and bacteria work in conjunction with the grass roots to supply nutrients to the grass so it recovers faster. Apply using a watering can at the rate of 20ml in 10 litres of water to 10sqm of turf.
• To encourage healthy grass apply Organic Lawn Fertiliser. Lawns get hungry, so it is important top feed them. These Organic Lawn Fertilisers are great value for money as you only need 3 applications a year unlike cheaper feeds, which have to applied every 4-6 weeks and can therefore work out more expensive in the long run. Apply our Spring / Summer Lawn Fertiliser 2 times – once in the spring and then again in the summer and then apply a final application of the Autumn Lawn Fertiliser in Sept / Oct.

Reseeding bare patches – simply rake the surface and re-sow using Lawn Repair Sticks. These clay-coated grass seed make repairing damaged areas of lawn much easier. Each clay coated Lawn Repair Stick contains 5-20 lawn seeds, which are scattered over the area to be repaired – there is no need to prepare the soil or cover with soil. These clay coated Lawn Repair Sticks will not blow away, will not be eaten by birds and insects and have a much higher germination rate than traditional grass seed. Sow between April and September at a rate of 30-80g per sqm. These lawn repair sticks are ideal for repairing lawns damaged by pests and pets. 950g repairs up to 20 sqm. Unlike normal grass seed they

• Will not blow away.
• Will not be eaten by birds.
• Have a much higher germination rate than traditional grass seed.

Summary – You now have the power to control leatherjackets naturally with products that are safe for you, children, pets and wildlife, but don’t just take my word for it just read what some of your fellow gardeners say :-

“After losing an entire lawn to Leatherjackets in 2016, I started using the Nematode product twice a year. Since then my lawn has been untouched. This year I had an additional problem with large numbers of very large slugs. Once again Green Gardener provided the cure.” Ian Flockhart

“Didn’t really expect the product to work however it seems to have done the job. Have only seen one live leatherjacket since applying the product.” Eleanor

“Green Gardener many thanks for all the help and advice that you have given me these last few years regarding the devastation caused by Leatherjackets to my lawn on a number of occasions, I have used Root Success along with your Leatherjacket killer and the results were absolutely spectacular. The lawn is now looking incredibly healthy, I cannot praise Root Success enough, a fantastic product, I have now ordered 2 further bottles. Green Gardener your passion, commitment and dedication in educating us amateur gardeners with your knowledge and products is much appreciated, you are a credit to your profession and great ambassadors for your company, Well done! and thanks you for Root Success.” Philip Jones

The post Saving your lawn from Leatherjackets by John the Green Gardener appeared first on Green Gardener.

A. Thanks for the message and it is always best to treat Leatherjackets in the autumn i.e. now as this is when the leatherjackets are newly hatched and the most susceptible to the nematodes. You can treat in April, but the leatherjackets are much more mature and much harder to kill so you need to apply the treatment at double strength. Therefore aim to treat in the autumn each year as you will get better results and the treatment goes further i.e. it treats 100 sqm when applied now but only 50 sqm in the spring (applied at double strength). Please CLICK HERE to find out more.

The post Customer Question – Applying Leatherjacket Killer appeared first on Green Gardener.