Sundew and Butterwort Decline in Terrarium: Diagnosis and Recovery

A college student in Grand Forks, ND grew D. aliciae and P. moranensis in a sealed terrarium with fans. Sundew produced mutant leaves; butterwort flowers aborted. No visible pests/mold.

Terrarium Problems

• Stagnant air → fungal/pest buildup.
• Humidity obsession is misguided – many grow tropical CP in open, dry homes successfully.
• Nutrient deficiency possible in closed systems.

Diagnostic Approach

1. Inspect closely – hand lens for mites (undersides, soil surface).
2. Treat "as if" – apply one treatment at a time, wait 1–2 weeks.
   • Neem for fungus/pests.
   • Weak fertilizer (¼ tsp/gal) for nutrition.
3. Transition to open culture – pots in trays, acclimate over weeks.

Fan Concerns

Gentle air movement is beneficial; avoid 24/7 direct blasting. Wild plants experience wind.

Resources

Grow Carnivorous Plants Vol. 2 (tropicals, acclimation). Care sheets at cobraplant.com.