Different varieties of the plant produce fruit of different size, shape and color, though typically purple. There are even orange varieties.
Solanum melongena var. esculentum common eggplant, with many cultivars
Solanum melongena var. depressum dwarf eggplant
Solanum melongena var. serpentium snake eggplant
The most widely cultivated varieties (cultivars) in Europe and North America today are elongated ovoid, 12–25 cm wide (4½ to 9 in) and 6–9 cm broad (2 to 4 in) in a dark purple skin.
A much wider range of shapes, sizes and colors is grown in India and elsewhere in Asia. Larger varieties weighing up to a kilogram (2.2 pounds) grow in the region between the Ganges and Yamuna rivers, while smaller varieties are found elsewhere. Colors vary from white to yellow or green as well as reddish-purple and dark purple. Some cultivars have a color gradient, from white at the stem to bright pink to deep purple or even black. Green or purple cultivars in white striping also exist. Chinese varieties are commonly shaped like a narrower, slightly pendulous cucumber, and were sometimes called Japanese eggplants in North America.
Oval or elongated oval-shaped and black-skinned cultivars include Harris Special Hibush, Burpee Hybrid, Black Magic, Classic, Dusky, and Black Beauty. Slim cultivars in purple-black skin include Little Fingers, Ichiban, Pingtung Long, and Tycoon; in green skin Louisiana Long Green and Thai (Long) Green; in white skin Dourga. Traditional, white-skinned, egg-shaped cultivars include Casper and Easter Egg. Bicolored cultivars with color gradient include Rosa Bianca and Violetta di Firenze. Bicolored cultivars in striping include Listada de Gandia and Udumalapet. In some parts of India, miniature varieties (most commonly called vengan) are popular. A particular variety of green brinjal known as Matti Gulla is grown in Matti village of Udupi district in Karnataka state in India.
In tropical and subtropical climates, eggplant can be sown directly into the garden. Eggplant grown in temperate climates fares better when transplanted into the garden after all danger of frost is passed. Seeds are typically started eight to ten weeks prior to the anticipated frost-free date.
Many pests and diseases which afflict other solanaceous plants, such as tomato, pepper (capsicum), and potato, are also troublesome to eggplants. For this reason, it should not be planted in areas previously occupied by its close relatives. Four years should separate successive crops of eggplants. Common North American pests include the potato beetles, flea beetles, aphids, and spider mites. (Adults can be removed by hand, though flea beetles can be especially difficult to control.) Good sanitation and crop rotation practices are extremely important for controlling fungal disease, the most serious of which is Verticillium.
Spacing should be 45 cm (18 in.) to 60 cm (24 in.) between plants, depending on cultivar, and 60 cm to 90 cm (24 to 36 in.) between rows, depending on the type of cultivation equipment being used. Mulching will help conserve moisture and prevent weeds and fungal diseases.
The flowers are relatively unattractive to bees and the first blossoms often do not set fruit. Hand pollination will improve the set of the first blossoms. Fruits are typically cut from the vine just above the calyx owing to the somewhat woody stems. Flowers are complete, containing both female and male structures, and may be self pollinated or cross pollinated