Eggplants are attractive, tender herbaceous perennials normally grown as annuals. Their purple flowers and large, purple-tinged leaves combine with colorful fruit to make them a stunning addition for a vegetable or flower garden. Eggplants are a warm-weather crop, thriving in heat and humidity that makes other crops wilt. It's best to grow eggplants in a part of the garden where you haven't grown related crops, including tomatoes, potatoes, and peppers, within the last 3 or 4 years. Many pests of eggplants are pests of these related plants too.
Choosing a site to grow eggplants
Select a site with full sun and fertile, well-drained soil. repare the garden bed by using a garden fork or tiller to loosen the soil to a depth of 12 to 15 inches, then mix in a 2- to 4-inch layer of compost.
Start plants indoors in flats or peat pots about 2 months before the soil warms up in your region, or buy nursery transplants just before planting. Cover planting beds with black plastic to warm heavy clay soils. Set out the transplants when all spring frost danger is past, spacing plants 18 to 24 inches apart.
Add an organic mulch to retain moisture and control weeds after the soil has completely warmed up, about 1 month after setting out transplants. Water plants during the summer if rainfall is less than 1 inch per week. Contact your local County Extension office for controls of common eggplant pests such as flea beetles, Colorado potato beetles, and tomato hornworms.
How to harvest eggplants
Most eggplants can be harvested when they are 4 to 5 inches long. The skin should be shiny; dull skin is a sign that the eggplant is overripe. Use a sharp knife and cut the eggplant from the plant, leaving at least 1 inch of stem attached to the fruit.