Baltimore Sun

Late blight found in Maryland

Late blight, the fungus that devastated tomato crops on the East Coast last summer, has been found on tomato plants in Maryland in a St. Mary's County greenhouse.

The University of Maryland's Extension service has sent representatives to gather plant material and determine whether this is the strain of blight that hit Maryland last year, or a more virulent strain that can winter-over. They will also check to see if the blight has spread beyond the greenhouse where the tomato plants were grown from seed.


Jon Traunfeld, head of the Home and Garden Information Center for the Maryland Extension service, said the late blight that hit Maryland last year can only survive on plant material and cannot endure our winter cold. So if gardeners and farmers did a good job of cleaning up their gardens last fall, they should be able to start the season disease-free. Our cold snowy winter, helped, too, he said.

However, if there were potatoes left in the ground over winter, the blight, which infects both tomatoes and potatoes, can survive on them.


Organic gardeners were especially hard hit last year because there is no effective organic fungicide to combat late blight. "Spray copper just doesn't do it," Traunfeld said.

Commercial farms, which used non-organic fungicides, did not suffer as much damage.

Traunfeld also advises gardeners to purchase their tomato plants, and other garden plants, from Maryland farmers in order to support those farmers.

It is possible that plants imported from southern states, where tomato plants can survive outdoors all winter, may carry infection.

Traunfeld is also advising Maryland gardeners to examine their tomato plants carefully and send photographs of any suspicious plant material -- or send the plant material itself --  to the Home and Garden Information Center. Or call 1-800-342-2507.

You can find photos and videos and more answers about late blight on the Grow It, Eat It website.