One way to have a healthy vegetable garden is to use varieties that contain resistance to certain diseases. Sound cultural practices also help to grow disease-free plants, practices such as crop rotation, enriching the soil with organic matter, using raised beds, rogueing (uprooting) diseased plants, and removing plant debris at the end of the season. Here is a partial list of hardy vegetable varieties and a few suggestions for home garden care.

Update: See also our new Vegetable Varieties for Gardeners website. It includes descriptions of more than 3,000 varieties, including disease resistance.

Beans

Green beans are very easy to grow, provided you use good seed and have quick emergence. Although susceptible to several diseases, rotation and raised beds will reduce soil-borne problems such as root rots and white mold. Varieties listed here are resistant to common bean mosaic, but they are susceptible to two prevalent virus diseases in New York (bean yellow mosaic and clover yellow vein). Rogue out plants that show mild green or prominent yellow mosaic before aphids spread the virus further.

Cucumbers

Of all cucurbits, cucumbers have the most disease resistance as a result of breeding. The concern is bacterial wilt, which is spread by cucumber beetles. Beetles can be reduced by constructing tents of fine cheesecloth or using floating row covers over young transplants and seedlings. Covers do need to be removed early to mid-season to allow for pollination. If the resistant variety listed is grown, angular leaf spot (ALS), cucumber mosaic virus, powdery mildew, and downy mildew are of no concern.

Summer squash

Summer squash are currently susceptible to powdery mildew and several virus diseases, but resistant varieties will shortly be released. In the meantime, tolerate mildew, plant an extra plant, and rogue if you get mosaic. The yellow varieties listed here have a gene that keeps them yellow when other yellow squash will turn speckled green from a common, though harmless, virus.

Eggplant

Verticillium wilt (VW) is the major disease of eggplant. This is a soil-borne disease which can survive for years, so rotation is required to achieve a good crop.

Peppers

The main disease of pepper grown in home gardens is cucumber mosaic. Rogue diseased plants to prevent aphid spread of this virus. Maintain adequate moisture to prevent blossom end rot.

Tomatoes

Almost all gardeners grow tomatoes for their own use and for use by their friends. Most varieties offer resistance to Fusarium wilt (F1 & F2), Verticillium wilt (VW), and rootknot nematodes (RN). Early blight is very common, especially if gardeners can't rotate over a large area.

Early maturing varieties are very susceptible and serve as a source of infection for later maturing types. Therefore, early varieties should be separated from later varieties by a good distance. If this is not possible, rogue out (uproot and destroy) any plant when blight becomes excessive. And select seedlings free of target-shaped lesions to avoid introducing early blight into the tomato patch.

Home gardeners who fail to rotate can also expect to find Septoria leaf spot. This disease prefers cool, moist (rain and dew) conditions. Gardeners can reduce its spread by removing lower, infected leaves early in the season. Look for beige lesions with black specks in the middle (the source of spores that is spread by splashing rain or careless watering), surrounded by a narrow yellow halo. Be sure to remove and destroy all tomato debris at the end of the season to reduce carryover of disease from year to year.

Prepared by:

Dr. Thomas Zitter, Associate Professor, Department of Plant Pathology, Cornell University, Ithaca, NY 14853