Scab is seed-borne and also survives in the soil. Develops in warm, wet weather after midseason. Spores can spread over long distances when the air is moist.
Plant cucurbits where others have not been planted for 2-3 years. Plant in unprotected areas where breezes and sunshine are not restricted. This allows leaf surfaces to dry more quickly, reducing infection. Begin applications of a copper soap fungicide before scab normally appears. We recommend Soap-Shield Flowable Liquid Copper Fungicide.