I've written quite a bit about late blight lately, and today received a strong warning from Meg McGrath, the Cornell University plant pathologist who is monitoring the disease in our area. She says late blight is progressing east through the North Fork:
"I would greatly appreciate your help getting the word out to gardeners that they need to inspect their tomatoes and potatoes because late blight has been found in more locations, and thus it is likely in additional places. We all need to work together to manage this so we can minimize the impact to all, especially all the farmers on the North Fork trying to make a living from these crops. So far late blight has been confirmed in both tomatoes and potatoes, farm and garden plants, from Riverhead to Mattituck. New symptoms could be starting to develop now as it has been a week since the rainy weather that provided the pathogen ideal conditions to spread and infect new plants. One week is the time it takes from infection for symptoms to appear."
Please get out there and inspect your plants. Here's an identification guide to help you determine if they're affected.
McGrath also has launched a new informational brochure on her website at www.hort.cornell.edu/lateblight. Click the link in the upper right corner.
If you suspect your plants are affected, bring them to one of the two Suffolk CCE clinics for diagnosis — 423 Griffing Ave., Riverhead, or the CCE office at Bayard Cutting Arboretum, 440 Montauk Hwy., Great River. It will help you because if your plant does not have late blight, you'll know you won't have to yank them out. And it will help us all to help the CCE track where the blight is surfacing.
Photo: Leaf lesions that can indicate late blight.