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Sudden Sundew Collapse: Fungus Gnat Larvae in Soil, Not Light or Water

Diagnosis: Fungus Gnat Infestation

Rapid, simultaneous decline of multiple sundews (while Nepenthes thrive) points to soil pests, not environment. Adult gnats caught on leaves confirm it. Larvae eat roots.

Critical Discovery: Nepenthes in Same Water Tray = Cross-Contamination

Nepenthes soil (coconut husk) breaks down in standing water, releasing nutrients that poison sundews. Never sit Nepenthes in water trays.

Treatment

Spray all soil with water-based insecticide (Safer Brand pyrethrin). Repeat in 7 days.

Move Nepenthes out of water trays immediately.

Nursery will replace lost sundews in next shipment.

Prevention

Monthly/bimonthly spray with natural products (Orange Guard, pyrethrin). Wet soil always attracts gnats.

Carnivorous Plants: Plants Around a Chlorinated Pool: Salt Is the Real Enemy; Sarracenia in Winter Rain: Submersion Tolerance; Cape Sundews Dying Despite Good Care: Troubleshooting Checklist; Hard Water Damage Mimicking Dormancy in Tropical Sundews: Repotting and Water Verification; Carnivorous Plants Dying? Check Your Peat and Perlite Brands; Deionized Water for Carnivorous Plants: Testing and Validation; Do You Need to Let Tap Water Sit Before Watering Plants?; Dracaena Winter Decline: Water Quality and Watering Fixes; Watering Houseplants: Why a Schedule Doesn't Work; Sudden Container Plant Collapse: Soil Moisture Extremes and Diagnostic Protocol

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Sudden Sundew Collapse: Fungus Gnat Larvae in Soil, Not Light or Water

Critical Discovery: Nepenthes in Same Water Tray = Cross-Contamination Nepenthes soil (coconut husk) breaks down in standing water, releasing nutrients that poison sundews. Never sit Nepenthes in water trays.

Treatment Spray all soil with water-based insecticide (Safer Brand pyrethrin). Repeat in 7 days. Move Nepenthes out of water trays immediately. Nursery will replace lost sundews in next shipment.

Prevention Monthly/bimonthly spray with natural products (Orange Guard, pyrethrin). Wet soil always attracts gnats.

Critical Discovery: Nepenthes in Same Water Tray = Cross-Contamination

Nepenthes soil (coconut husk) breaks down in standing water, releasing nutrients that poison sundews. Never sit Nepenthes in water trays.

Treatment

Spray all soil with water-based insecticide (Safer Brand pyrethrin). Repeat in 7 days.

Move Nepenthes out of water trays immediately.

Nursery will replace lost sundews in next shipment.

Prevention

Monthly/bimonthly spray with natural products (Orange Guard, pyrethrin). Wet soil always attracts gnats.