Early Cucumber Planting Protects Against Downy Mildew Disease

Web Admin Cucurbits, Disease, Research


Early cucumber planting helps avoid downy mildew disease and increases yields, according to Clemson plant pathologist Tony Keinath in The South Carolina Grower.

Tony Keinath

Keinath said producers should plant within one month of recommended planting dates which avoids downy mildew disease that is most prevalent between May 15 and June 15. In an experiment in 2021 at Clemson’s Coastal Research and Education Center in Charleston, South Carolina, seeded cucumbers on March 24 yielded twice as much as cucumbers seeded on April 15.

Yields were the same for sprayed and non-sprayed early-seeded cucumbers. They were also ready for harvest on May 19 before downy mildew was first observed on May 25.

Some early-season cucumbers succumbed to freezing temperatures on April 3 and had to be replaced with transplants. But the yields that produced fruit before the summer heat exceeded the transplant costs.

If growers plant between mid-April and mid-May, a resistant cultivar must be planted if conventional fungicides will not be implemented. Bristol slicing cucumber and Citadel or Peacemaker pickling cucumbers provided the best resistance and yielded well in North Carolina and South Carolina, even without fungicides.

For more information see this Clemson News Release.