Brownish water-soaked spots appear on leaves. They enlarge rapidly, turn black, and kill the leaves, then the leafstalks and main stems. In moist weather, gray mildew grows on the lower surfaces of leaves. Both in the ground or in storage, brownish purple spots that become a wet or dry rot infect the tuber skins.
If late blight is an annual problem in your area, apply a fungicide labeled for this disease, following label directions. Use drip or furrow irrigation. Wait at least a week after plants die naturally before digging the tubers. This allows time for the spores to die. Handle the tubers gently to avoid wounding them. Clean up and destroy plant debris after harvest. Plant certified disease-free seed pieces.
©2002-2012 The Scotts Company LLC, all rights reserved.
® and ™ denote trademarks owned by or licensed to The Scotts Company LLC, its affiliates, or partners.
The Global Professional business group and its subsidiaries of The Scotts Company LLC were purchased by ICL in February 2011. This is the USA consumer products site forThe Scotts Company LLC. For information about ICL or Scotts® Professional products, please visit http://www.scottsprofessional.com.