Basal Rot (Bulb Rot)
Fusarium spp.
1 host plant · Fungal
Last updated
This profile contains verified disease data from extension databases. Regional field notes and expert review are in progress.
Bulbs or corms soften and rot at base with foul smell. Use well-draining soil, avoid overwatering, and choose disease-free bulbs.
Reduce moisture around affected tissue by improving drainage and air circulation. Remove rotted material cleanly and dispose of it away from the planting area. Avoid wounding healthy tissue during cleanup, as fresh wounds create new entry points. If the problem keeps returning, evaluate whether the site is too wet or poorly drained for the species you are growing.
Quick Reference
Management
Infection during warm growing season (May–Sept). Rot development visible in storage (cool season when fungus remains active). Replanting infected bulbs perpetuates problem. BBCH 10–89.
Root entry and bulb rot initiation in warm, moist soil (75–85°F). Wet conditions, poor drainage, and waterlogging favor infection. Cool maritime storage conditions slow but do not prevent fungal growth.
Cultural Controls
- Source bulbs from disease-free suppliers or certified stock.
- Avoid planting in warm, wet soil or in poorly drained sites.
- Provide good drainage and avoid overwatering.
- Remove and destroy infected bulbs during storage.
- Do not replant in infested soil for at least 1-2 years.