Sarracenia leucophylla 'Tarnok' Rhizome Rot: Botrytis and Water Quality

Diagnosing Brown Rhizome in Sarracenia 'Tarnok'

A Salem, OR grower finds their S. leucophylla 'Tarnok' rhizome turning brown after a year in a greenhouse with fluorescent lights (few hours/day), a small heater, and well water. Soil is 1:1 peat/perlite.

S. leucophylla 'Tarnok'

Expert Diagnosis

Jeff Dallas: Brown, mushy rhizome indicates Botrytis (grey mold) fungal infection—common in humid greenhouses during PNW winters. Unpot and check for white, firm tissue. If any living parts remain, cut away brown, spray with sulfur fungicide, and repot in fresh media. If entirely brown, the plant is dead.

Contributing Factors

• Well Water: Hard water (high minerals) builds up in tray systems, weakening plants and increasing disease susceptibility. Rainwater flushes minerals outdoors; greenhouses trap them.
• Greenhouse Wintering: Sarracenia tolerate mid-20s°F outdoors. Greenhouses promote fungal growth. Keep plants outside in rain/UV light; only shelter during severe cold (teens).

Lesson Learned

Even experienced growers lose plants by over-protecting them in greenhouses. Outdoor cultivation is usually safer for temperate CP.