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Fungus Gnat Larvae in Venus Flytraps: Spinosad and Mosquito Dunks

Alan returned with a follow-up on his Dionaea 'King Henry' flytraps showing small holes and a worm-like culprit he identified as fungus gnat larvae. The pests were chewing nectar glands and affecting new growth, but only on flytraps—pitcher plants and sundews were unaffected.

Recommended Controls

Jeff Dallas referenced his previous answer (original thread) and added a highly effective option: Spinosad.

Spinosad: A biological insecticide derived from soil bacteria, effective against chewing/sucking insects. Widely available at garden centers under various brands.
Mosquito Dunks (Bti): Place dunks in watering containers; they release Bacillus thuringiensis israelensis toxins specific to fungus gnats and mosquitoes. Safe for plants, pets, and beneficial insects. Used routinely in Sarracenia Northwest's own pools and greenhouses.

Jeff also recommended their podcast on safe insecticides for application guidance.

Good Growing!
Jeff Dallas
Sarracenia Northwest
www.growcarnivorousplants.com

Carnivorous Plants: Planting Shrubs in Slow-Draining Soil; Do Venus Flytraps Die After Flowering? Myth vs. Reality; Venus Flytrap 'King Henry' Early Growth: Flower Removal and Light Correction; Growing Venus Flytraps Under Artificial Light: Limits and Dormancy Planning; Venus Flytrap Seed Sowing: Peat/Sand Mix, Boiling Water Sterilization, and Fresh Seed; Venus Flytrap Seedling Dormancy: Let Nature Decide the First Year; Venus Flytrap Trap Closure Issue: Insufficient Light Diagnosis; Drosera regia (King Sundew) Leaf Tip Burn: Cool Nights and Media Matter; Venus Flytrap Flowering: Myth vs. Reality—When to Cut the Stalk; Complete Guide to Growing Venus Flytraps

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