Clean seed is produced in dry inland areas of California. Copper containing sprays can help control the disease. Copper fungicides such as Kocide 101, Kocide 606, Champion, or Champion Flowable can be used by commercial growers. Homeowners can use Bordeaux Mixture. These fungicides should be applied in strict accordance with label instructions.
Current recommendations are available at county extension offices.
Copper sprays should not be continued in dry weather, especially hot, dry weather, because the sprays may cause plant injury. Debris from the crop should be destroyed to decrease overwintering and spread of the disease to other fields the next year. Avoid excessive overhead irrigation or excessive amounts of nitrogen fertilizer. Do not work the cucumber field when plants are wet since water helps spread the disease. Some cucumber varieties have resistance or tolerance to angular leafspot.