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Fungus Fly Killer Nematodes


What Are Fungus Gnats?

The Fungus Fly, also known as the Sciarid Fly, can cause severe damage to many plants including house plants and plants being propagated. These tiny flies will lay eggs in compost or soil, from which larvae develop. The larvae often feed on young plants and seedlings at propagation and are a very common pest in house plants. Damp conditions and organic plant matter will provide an ideal breeding ground for the larvae, which will feed on plant roots causing damping off and seedling collapse. The larvae, at large numbers, can also spread soil-borne diseases such as Pythium. Once the larvae develop into adults they become nuisance pests, forming small clouds of flies when disturbed. 

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

Fungus Fly Killer contains Steinernema feltiae nematodes for the effective biological control of Fungus / Sciarid Fly. The nematodes enter the larvae via a natural opening, like the mouth, and feed on the contents of the larvae. 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?

Apply your Fungus Fly Killer Nematodes when damage to plants is observed or when Fungus Fly activity has been observed. Fungus Fly can occur all year round and can be treated at any time they occur.

How Many Nematodes Do I Need?

The Fungus Fly Killer Nematodes are available in 6 different pack sizes as detailed below:

- 1 x 5 million nematodes to treat up to 10m2 (or up to 25 house plants)

- 1 x 10 million nematodes to treat up to 20m2 (or up to 50 house plants) 

- 1 x 25 million nematodes to treat up to 50m2

- 2 x 25 million nematodes to treat up to 100m2

- 1 x 250 million nematodes to treat up to 500m2

- 2 x 250 million nematodes to treat up to 1000m2

What Conditions Do The Nematodes Require?

Choose a humid or wet day to apply your Fungus 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.

Soil or compost temperatures should be above 10℃ for the nematodes to be active. 

How Do I Apply The Nematodes?

For small packs (5 and 10 million):

1. Open and empty contents of the 5 million sachet into a 0.5 litre (500ml) bucket, or container, of lukewarm water and mix thoroughly. For a 10 million unit mix the solution in a 1 litre bucket (1000ml) and mix.

2. Add nematode concentrate to a watering can and add water. This should be at least 0.5 litre of water for the 5 million pack concentrate, and add at least 1 litre of water for the 10 million pack concentrate.

3. Mix the concentrate solution and extra water for one minute to distribute the nematodes evenly in the solution. Apply immediately after mixed.

4. Pour and apply the solution into the Houseplant pots, seed trays, or containers, directly into the growing media / compost, using all the solution between the treated pots.

For larger packs (25 million plus):

1. 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. Add 0.5L of the nematode concentrate to a watering can 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 up to 8L of water.

3. One pack of 50sqm nematodes will make 5 watering cans (including concentrate solution).

4. Spray the soil or compost and ensure plenty of the solution is applied directly onto the Fungus Fly larvae. If applying to pots, make sure nematode solution reaches root zone at the bottom of the pots. 

One watering can treats up to 10sqm, and the entire solution treats up to 50sqm.

Ensure the soil is moist for 2 weeks since application.

Repeat applications may be required after 4 weeks to prevent the build up of fresh Fungus Fly larvae.

Full application 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.

Fungus Fly Killer Nematodes are harmless to humans, pets and wildlife, and safe to apply to edible plants.

Use Our Yellow Sticky Traps To Catch Adult Fungus Flies

Black adults of Fungus / Sciarid Fly can reach high levels. It is best to use some of our yellow sticky traps in combination with your nematode treatment to prevent the build up of a large infestation. See our Eco Sticky TrapsYellow Sticky TrapsExtra Large Yellow Sticky Traps, or our Mini Sticky Traps (for smaller pots).

See Also Our Hypoaspis Miles Predators For Complete Fungus Fly Protection 

Hypoaspis miles are small predatory mites that inhabit the soil or compost surface around the plant stem and feed on the eggs and larvae of Fungus / Sciarid Flies. Utilise these predators in combination with your Fungus Fly Killer Nematodes for the complete protection against Fungus Fly infestation. The Hypoaspis miles product listing can be found here.

Customer Reviews

Based on 9 reviews Write a review

Customer Reviews

Based on 46 reviews

This product is fantastic and got rid of the pesky fungus gnats

Fungus flies entirely GONE!

I've noticed fungus flies in my flat for a several years, eventually working out the source of them as my potted plants. They were very irritating as they seemed to be attracted especially to my face! I've been using sticky traps for about a year which has helped but this year one trap collected millions of the little blighters (probably a couple of hundred, realistically). After applying nematodes to all my pots a couple of weeks ago I saw far less of them flying around, and since replacing the sticky traps a week ago - absolutely none collected! I hope that they won't return and will keep monitoring with traps.

Mandy Jackson
Easy to use.

Does the job quickly. A bit expensive but cheaper than keep buying sticky traps.

No more fungus gnats!

They arrived quickly, I followed the instructions and they worked perfectly! Finally got rid of the annoying fungus gnats!
My only negative comment is that I thought they were quite expensive… but they worked, unlike everything else I tried!


Product arrived very quickly , simple easy to follow instructions. Used the product straight away and have had no evidence of a further infestation 😃
Would recommend if you are having a fly problem in your home.