Pests & diseases › Onion White Rot
Onion White Rot
Devastating soil-borne fungal disease of onions, garlic and leeks. White fluffy growth on bulb base.
Symptoms
- Yellow, wilting foliage
- Soft white fluffy mould on bulb base
- Tiny black resting bodies (sclerotia) in the mould
- Plants pull out easily — rotten roots
Lifecycle
Sclerotia survive in soil for 15+ years. Triggered by chemicals released by onion roots.
What to do
- Pull and bin (NEVER compost) every affected plant
- Wash boots and tools — don't spread soil
If it's bad
- None — no cure exists
Stop it coming back
- Buy only from trusted seed and set suppliers
- Never bring soil onto your plot from elsewhere
- Once infected, the bed is out of alliums for 15 years — accept it and rotate widely
- Grow alliums in containers if your soil is infected
Crops it goes for
Plan the plot, track every sowing, cook the harvest
Sowing reminders and harvest forecasts for your own frost dates, the Seed Tin, Scan Centre for any label or packet, and the Potty Mouth Garden Club. Free to start.