Felti - against fungus flies

Regular price

Felti is the natural enemy of fungus fly larvae (also known as fungus gnats) in the potting soil.

For complete control of fungus flies, we recommend using small trapping cards in combination with Felti.

Please note: If the temperature is above 25 degrees, we will send Carpo instead of Felti nematodes. This species is more vital at these temperatures and therefore more effective against fungus flies.

Free delivery from €20 within the Netherlands. Standard shipping costs are €2.95

Ordered before 3:00 PM on working days, shipped the same day

Package late? Do not panic! The Heroes can take a beating.

Product information

Felti are microscopic nematodes that occur naturally in Dutch soil. The small worms penetrate the larvae in the potting soil and secrete a bacterium that kills the fungus fly within 2-3 days. Felti is known as a nematode that is effective at relatively low temperatures.

The product is supplied in powder form. Felti nematodes can easily be dissolved in water and distributed over the potting soil with a watering can. An easy and natural way to combat fungus flies, without harming plants, bees, birds and mammals!

1. Dosage
Assuming a houseplant with a pot of 40 cm diameter.

• 5 million is enough for 25 houseplants
• 10 million is enough for 50 houseplants
• 25 million is enough for 100 houseplants

2. When to bet
Felti works best when the soil temperature is between 10 °C and 25 °C. Do not expose to direct sunlight: apply in the evening, morning or during cloudy weather. After application, it is important to keep the soil slightly moist for another two weeks, so that the nematodes do not dry out.

3. Shelf life
It is advisable to use the nematodes as soon as possible. Do you want to keep the nematodes longer? Then store them in the refrigerator between 4ºC and 8ºC. The nematodes have a shelf life of 1 week after receipt, provided they are refrigerated. Do not store the water solution again.

4. Location
Felti can easily be applied to the potting soil of houseplants with a watering can.

5. Repeat treatment
A one-time application does not guarantee that the fungus flies will disappear from the houseplants forever. Multiple repeat treatments are recommended to break the life cycle.

Under optimal conditions, Felti can kill a fungus fly larva within 1-2 days. In practice, the nematode will have to find the larva first. After 1-2 weeks there are fewer mourning flies present.

For complete control, the use of Sticky Leaf trapping cards is recommended. This also tackles the adult mourning flies and prevents the adult flies from laying eggs.

Felti occurs naturally in Dutch soil. Felti is a 100% natural product. The nematodes are not harmful to people, pets, bees, birds or earthworms.


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Why Insect Heroes?


It is the most natural pest control available


They only attack the unwanted critters and leave the rest alone


See with your own eyes how nature does its work


Protect bees, butterflies and other beneficial insects

Customer Reviews

Based on 1 review
The one and only salvation for fungus gnats

I bought this after trying literally everything against fungus gnats because I was hesitant with the idea of “suspicious nematodes in my pots’. In 3 days after I watered the plants with the solution of nematodes, I literally saw no more flying ones, and neither those who were always noticed on the surface of the soil. Piece of mind. I keep the sticky traps just to catch the new incomers, but it seems like they are just not flying around anymore. Big thank you for this package. I have 1 plant at work to treat too, and I will use this package straightaway. Mind that you cannot really store/keep the nematodes powder more than a week if you did not need to use it all for many plants. It is a pity, but it is what it is and it saved my house plants!

Hi O.G.,

Thank you for your wonderful review! We're thrilled our nematodes solved your fungus gnat problem so quickly. It's great to hear your plants are thriving again. If you need further assistance, we're here to help!