Fungal
White Rot
A soil-borne fungal disease of alliums causing fluffy white fungal growth and black sclerotia at the base of bulbs, rotting roots and killing plants.
Symptoms to Look For
- Plants yellowing from older leaves inward; pulling up easily with few roots
- Dense white fluffy fungal growth at the bulb base with small black sclerotia embedded in it
- Entire bulb rotting from the base upward in severe cases
Affected Plants
OnionGarlicShallotLeekChive
Organic Solutions
Trichoderma biocontrol
Apply Trichoderma viride or T. harzianum-based product to the seed trench at planting to establish competing beneficial fungi.
Remove infected plants and soil
Dig out affected plants including a generous root ball of surrounding soil and dispose of in household waste, not compost.
Prevention
- Avoid growing any allium on infected ground for at least 15 years - sclerotia survive in soil for decades
- Never share soil, tools, or allium material from an infected plot
- Lure sclerotia to germinate and die without a host by watering infested soil with a dilute garlic extract 6 weeks before planting
Garden, by Willowbottom recommends only organic, wildlife-friendly solutions. No synthetic pesticides, no harmful chemicals - ever.