Downy mildew has been found on cucumber in Haywood County, NC as of July 31, 2026. This is the first report in the western region in 2026. Growers in this region should scout diligently and transition fungicide applications on cucumber crops to those highly effective against downy mildew. See fungicide guidelines described by Dr. Frank Louws in his first report of cucumber downy mildew in NC of 2026: https://plantpathology.ces.ncsu.edu/news/cucumber-downy-mildew-confirmed-in-lenoir-countyfirst-north-carolina-report-of-2026/

The clade of downy mildew pathogens (clade 2) that infect cucumber do not pose a threat to squash, pumpkin, or watermelon, which are infected by clade 1 isolates. Thus far, there have been no reports of downy mildew on squash, pumpkin, or watermelon in NC.

For more information about this disease, see the NCSU factsheet on cucurbit downy mildew: https://content.ces.ncsu.edu/cucurbit-downy-mildew