Sciarid Fly Predators (Steinernema Feltiae) Tray of 50 Million - Biological Fungus Gnat Control
Best for: growers with a sciarid fly (fungus gnat) problem in soil or coco who want a biological, chemical-free fix.
Our thoughts
Nematodes tackle the actual source of a sciarid fly problem - the larvae living in your growing medium - rather than just the adult flies you see hopping around on top. Bioline is an established name in biological pest control, and this is a proper commercial-grade product rather than a hobby-shelf afterthought.
This tray contains 50 million infective juveniles of the insect-killing nematode Steinernema feltiae. Mixed with water and applied as a drench, the nematodes move through the water films around soil particles, actively seeking out and infecting sciarid fly larvae living in the root zone. Once inside a larva, the nematode releases symbiotic bacteria that kill it within a day or two. Adult sciarid flies are usually the visible sign of a problem, hopping across the compost surface, but it's the larval stage that does the real damage - feeding on plant roots and leaving them open to root diseases like Pythium, which can wreck an entire crop if left unchecked. The same nematodes can also be applied as a foliar spray to tackle thrips (including Western Flower Thrips), leaf miners and some scale insects.
How it compares
It's a biological alternative to chemical soil treatments.
- vs chemical soil drenches: works biologically, leaving no chemical residue and posing no risk to beneficial insects or edible crops
- vs other Steinernema feltiae products (Nemasys, SuperNemos): same active species and mode of action - Bioline's product is a commercial-grade supply used across professional horticulture
- vs sticky traps: traps only catch adult flies; nematodes target the larvae in the medium, where the actual root damage happens
In plain terms: this deals with the cause of a sciarid fly problem, not just the flies you can see.
Usage guidance
Mixing
Dissolve the tray's contents in water following the instructions included with the pack, and use it fairly promptly once mixed for best results.
Applying as a soil drench
Water the mixed solution into the growing medium so the nematodes reach the root zone where sciarid larvae feed.
Applying as a foliar spray
For thrips, leaf miners and scale, spray onto foliage in cooler conditions with indirect light rather than direct midday sun.
Storage before use
Keep refrigerated (not frozen) and use within the timeframe stated on the pack - these are living organisms, not a shelf-stable chemical.
Coverage
This 50 million pack is sized for a moderate treatment area - check the pack guidance for your specific area, and repeat or scale up for larger spaces.
Technical specifications
- Active organism: Steinernema feltiae infective juveniles
- Pack size: 50 million per tray
- Primary target: sciarid fly (fungus gnat) larvae
- Also effective against: thrips (foliar use), leaf miners, some scale insects
- Format: living nematodes in a carrier medium, mixed with water before use
- Mode of action: infects host larvae, releases symbiotic bacteria
- Storage: refrigerate before use - living organism, use promptly
- SKU: 1459
Who this is for
- Growers dealing with fungus gnats/sciarid flies in soil or coco
- Organic or chemical-free growers wanting biological pest control
- Anyone worried about root disease risk (Pythium) from larval root damage
- Growers wanting a biological option against thrips via foliar application
Our take
This is a properly effective way to deal with sciarid flies at the root of the problem, literally. It's biological, leaves nothing toxic behind, and covers more than one pest if you use it as a foliar spray too.
One we sell a lot of for growers who've spotted flies hopping around the compost and want to sort it properly rather than just spraying the adults.
