FREE DELIVERY FOR ALL ORDERS OVER £50 (Excluding Bumblebee Colony Orders & Product Subscriptions)

Onion Fly Killer Nematodes

Treatment Size

What Are Onion Flies? 

The Onion Fly (Delia antiqua), also known as the Onion Maggot, is a common pest that attacks allium plants, including OnionGarlic and Leek crops. The adult flies are small, measuring between 5-7mm, with a yellowish-grey body and clear wings.

Female Onion Flies lay eggs on necks of onion seedings, in the soil close to the base of onion plants, or on young leaves. The eggs hatch into Onion Fly larvae that tunnel into the bulbs of onions, damaging the foliage and the roots. These attacks lead to stunted growth, reduced yields and are sometimes even fatal for the plant.

What Are Onion Fly Killer Nematodes & How Can They Help?

Naturally and safely control your Onion Fly infestation with our Onion Fly Killer Nematodes, which are deadly to Onion Fly larvae but safe to humans, pets and wildlife. Dragonfli Onion Fly Killer contain Steinernema species nematodes that enter the Onion Fly larvae via a natural opening, like the mouth, and feed on the pest from inside it. A natural bacterium is produced by the nematodes inside the larvae, which kills it. Infected larvae will be completely broken down by the nematodes. The nematodes also reproduce inside the larvae, releasing more nematodes into the surrounding area.

When Should I Apply The Nematodes?

Onion Flies are likely to emerge from overwintering sites in May. The adult flies will then proceed to mate and lay eggs on leaves or at the base of the crop. The larvae will hatch approximately 3 days after the eggs have been lain and start feeding on the plants. It is therefore recommended that you apply your Onion Fly Killer Nematodes from May onwards and whenever Onion Fly larvae are identified in your soils.

How Many Nematodes Do I Need?

The 25million pack will treat an area of up to 50m2.

The 50million pack will treat an area of up to 100m2.

The 250million pack will treat an area of up to 500m2.

The 500million pack will treat an area of up to 1000m2.

If your plants have suffered severely from Onion Fly larvae damage, and the number of larvae within the soil is high, multiple applications of nematodes will be required to gain overall control. Consider applying Onion Fly Killer Nematodes every 2 weeks in the summer period.

What Conditions Do The Nematodes Require?

Choose a humid or wet day to apply your Onion Fly Killer Nematodes. Nematodes are UV-sensitive and will not survive long when exposed to bright, sunny conditions. Apply the nematodes early in the morning or early in the evening in order to utilise the optimum humidity levels. Avoid application in frosty conditions.

Soil temperatures should be above 13℃ for the nematodes to be active.

How Do I Apply The Nematodes?

To increase the effectiveness of your nematode treatment we always advise you pre water area to be treated with nematodes prior to application. The soil needs to be kept moist for nematodes to penetrate the soil and reach the Onion Fly larvae.

See also our Nemaflo carrier which will help aid the movement of the nematodes in the soil.

1. First open and empty the contents of your 25 million sachet of nematodes into a bucket or container of 2.5 litres of water and mix thoroughly.

2. Next, fill your watering can (fit with a coarse rose), or sprayer (hand held sprayers should suffice, with filters removed, or use our specific nematode applicator, the Nema Super Sprayer for optimum nematode application) with the mixed 2.5 litres of nematode concentrate and add another 5.5 litres of water so you are left with 8 litres of nematode solution.

3. Finally, spray your lawn with the nematode solution.

Continue to keep the soil moist for up to 2 weeks after application. Repeat applications may be required for severe infestations. Full instructions are provided on delivery. 

Can I Store Nematodes?

You can store unopened nematode packs in a fridge but it is best to ensure you apply your nematodes as soon as possible for the best results.

Onion Fly Killer Nematodes are harmless to humans, and safe to apply to edible plants.

Improve Soil Quality With OurSoil Boost Biostimulant

Consider the addition of Soil Boost which will also boost and help the development of beneficial microbial life in soils, improving root and plant health.

Customer Reviews

Be the first to write a review