Late Blight is worse than ever this year.  One of the most visible early symptoms of the disease are brown spots (lesions) on stems. They begin small and firm, then quickly enlarge, with white fungal growth developing under moist conditions that leads to a soft rot collapsing the stem.

Classic symptoms are large (at least nickel-sized) olive-green to brown spots on leaves with slightly fuzzy white fungal growth on the underside when conditions have been humid (early morning or after rain). Sometimes the border of the spot is yellow or has a water-soaked appearance. Spots begin tiny, irregularly shaped and brown. Firm, brown spots develop on tomato fruit.

Check your plants regularly.

Below are some helpful information sheets.  If you have further questions contact Steve VanderMark at the Extension office.  (315)379-9192 ext. 232.

Late Blight Fact Sheet

Rutgers Late Blight Fact Sheet

Late Blight of Tomato and Potato

Frequently Asked Questions

Below are some helpful links:

http://blogs.cornell.edu/hort/2009/06/26/late-blight-a-serious-disease-killing-tomatoes-and-potatoes-this-year/

http://plantclinic.cornell.edu/FactSheets/lateblight/late.htm

http://www.hort.cornell.edu/department/Facilities/lihrec/vegpath/lbfaq.pdf

http://www.hort.cornell.edu/department/Facilities/lihrec/vegpath/lbmisinfo.pdf