Scab is a disease of gladiolus caused by bacteria that penetrates the corm and then moves up the stem base. Scab causes corms to develop brown to black, irregular or round, sunken spots with shiny brittle, varnishlike bacterial exudates on the surface. Leaf bases have red or brown specks.
Solutions
Scab is favored by poorly drained, wet, warm soils. Provide good soil drainage. Don’t overirrigate or overfertilize. Control chewing insects in soil that injure corms. Remove and destroy infected plants.The pesticide information on this page may become out of date as products and active ingredients change or become unavailable. Some of the pesticides listed are only available for use by licensed pesticide applicators. No endorsements of named products are intended, nor is criticism implied of products not mentioned.
