If we were to make a list of favorite garden vegetables, you probably wouldn't find eggplant very near the top of the list. While it may not be as popular as the tomato, it does produce good yields of fruit, which can be used in a wide variety of dishes. In addition, it is somewhat attractive, and has been used on occasion in ornamental plantings.
Eggplant is another member of the nightshade family (solanaceae), which also includes tomatoes, peppers, and potatoes. Like other solanaceous crops, eggplants were once considered less-than-desirable as food, if not actually poisonous. In the 16th century, it was known as the "mad apple", because it was thought that consumption would lead to insanity.
Originally, eggplant was found in two regions of the world. Smaller-fruited types came from China, and larger-fruited types came from India. The name of "eggplant" was chosen because of the shape of the small-fruited varieties which are similar to eggs. Today, we can grow either type, or hybrids of the two types. This has led to a wide selection of sizes, shapes, and colors. There are even small, white varieties, which do come close to looking like eggs. These can make unusual ornamental plants.
Like tomatoes, eggplants love hot weather, and do their best during mid-summer. Daytime temperatures of 78 degrees are optimal. Nighttime temperatures are best above 68 degrees. Eggplants will grow in warmer weather, but may fail to set fruit if temperatures get too high. If drying winds accompany the high temperature readings, pollination may be prevented. However cooler weather will bring a return of fruiting. When fall arrives, eggplants slow their growth, and fruits do not develop.
The best time to harvest eggplant is when they are young, approximately 1/3 to 2/3 of their mature size. If you press lightly on the side of the fruit with your thumb, the flesh should readily spring back. If it does not, the fruit is too mature. Another indicator of maturity is the skin color. Fruit which is still optimal will have a high gloss, but over-mature fruit may look dull, with possible bronzing.
When selecting varieties to grow, choose those which have disease resistance. Some of the diseases which are problems in tomatoes can also attack eggplants, such as verticillium wilt. Be sure to rotate your crops each year, and this will lessen the likelihood of disease.
Insect pests can be a problem, especially flea beetles. These are small, black beetles, about 1/16 inch long. They feed on the leaves, making many small holes. In severe cases, they can actually destroy the plant. Even if your eggplant survives, they can still stunt the plant and reduce yields. If flea beetles are a problem, you will need to maintain a regular spray schedule in order to harvest a crop.
As a final thought, remember that these plants are normally vigorous growers, producing large fruits. This means that they will need plenty of moisture, especially on sandy soils. During the hot weather that makes them thrive, be sure to give them regular water. You'll soon be giving eggplant to your neighbors.
Tim Baker, Northwest Region Horticulture Specialist, University of Missouri Extension
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