Eggplants

The eggplant is probably a native of India, and has been cultivated for a long time. It is a member of the nightshade family, making it a close relative of the tomato,pepper and potato.

Climate Requirements

The eggplant is a very tender plant, requiring a long, warm season for successful production. The plants are killed by light frost and are injured by long periods of chilly,frostless weather. Plants should not be set out until all danger of frost has passed.

Fertilizer and Lime

Lime and fertilizer applications should be based on a soil test. In general, 2 pounds each of actual nitrogen, phosphorus, and potassium per 1,000 square feet of garden space is adequate. An additional application of one pound of actual nitrogen per 1,000 sq. ft. after the fruit has set may be helpful to maintain plant development. Soil pH should be maintained between 6.0 and 6.8.

Culture

The use of plastic mulch can increase the yield of eggplant by helping to warm the soil, by conserving moisture, and by controlling weeds. Plants may be planted in staggered double rows on each strip of plastic. Place the plastic on 5 foot centers and allow 18 inches between plants in each of the staggered rows. It is best to use transplants because of the need for a long, warm growing season,. These may be purchased or started in peat pots or pellets 8 to10 weeks before the anticipated planting time.

Pests and Diseases

Insect and mite pests of eggplant include flea beetles, Colorado potato beetle, aphids, and spider mites. Four-year rotations with non-related crops and the use of plants grown from disease-free seeds will help control some eggplant diseases. A particularly damaging disease in eggplant is Verticillium wilt, which can cause stunting in plants and wilting and dying of leaves. Avoid tomatoes, potatoes, peppers, okra, raspberries, or strawberries in rotation with eggplant.

Harvest

The fruits of the eggplant are edible from the time they are one-third grown until ripe. They remain edible for several weeks after they become colored and fully grown. Skin should be shiny; seeds inside should not be brown or hard. Harvest will continue over an extended period if the fruits are removed when they are well-colored and of adequate size. Cut the fruits from the plants, leaving large calyx (cap) and a short piece of stem on the fruit. Plants of most cultivars have sharp spines, so care is necessary when harvesting to prevent injury. 

Adapted from Ted W. Gastier, Ohio State University Extension, 2000