What is causing the edges of the leaves on my zucchini plants to turn black?

Asked June 15, 2015, 10:43 AM EDT

The edges of the leaves on my Zucchini plants are turning black. Any idea what could be causing this and what could be done to treat the condition?

Santa Clara County California zucchini problem

1 Response

To whom it may concern,

It is difficult to diagnose your problem based on this image alone, but you should consider powdery mildew and downy mildew as possibilities. Please visit these UC IPM webpages to confirm and learn about management:

http://www.ipm.ucdavis.edu/PMG/GARDEN/VEGES/squash.html

http://www.ipm.ucdavis.edu/PMG/GARDEN/VEGES/DISEASES/cupowerymildew.html

http://www.ipm.ucdavis.edu/PMG/GARDEN/VEGES/DISEASES/cudowneymildew.html

You also could submit a sample to your county's UCCE Master Gardener Help Desk program for free problem diagnosis and management advice: http://www.mastergardeners.org/ask-a-question

Best regards,

Andrew