Symptoms:
Spots on the leaves become covered
with a lavender or purplish mold. Requires cool
temperatures and rain or high humidity. Under
these conditions, onion leaves bend, resulting in
lower yields and bulb quality.
Solutions:
Grow onions in well-drained soil to
keep roots from getting soggy. To prevent the
spread of disease, wash tools and shoes after you
work in the vegetable patch. Remove weeds and
garden debris, which harbor insects that transmit
diseases. Check plants every few days for signs of
damage and destroy infected plants. Spray regularly
with a copper soap fungicide to reduce infection.
(Because of the continual emergence of new
leaves from the neck, timely and thorough spraying
will be required to keep new growth covered.)
We recommend Soap-Shield Flowable Liquid Copper Fungicide.