Eggplant, also known as aubergine by British and French gardeners, is a staple in the summer vegetable garden. This relative of potatoes and tomatoes has a meaty texture and delicate flavor that make it a favorite of vegetarians and omnivores alike.
Eggplant Varieties for the Organic Garden
Growing eggplant in the garden allows gardeners to try unusual varieties beyond the classic large dark purple type seen in grocery stores. For example, ‘Fairytale,’ an All America Selections winner, bears heavy yields of small bright violet fruits with few seeds and no bitterness. ‘Rosa Bianca’ is an Italian heirloom featuring ribbed fruits with white streaks. ‘Kermit’ looks more like a gooseberry than an eggplant, yielding two-inch green fruits with very firm flesh.
Planting and Fertilizing Eggplant
Eggplant is easy to start from seed, but gardeners must be aware of the sensitivity of young seedlings to cold conditions. It isn’t enough to wait until the last frost to place eggplants in the garden; seedlings will refuse to germinate and young plants will sulk in cold soil. Don’t place seeds or transplants outdoors until at least six weeks after the last possible frost dates.
Eggplants thrive in rich soil amended with ample amounts of compost or well-rotted manure. Gardeners should apply three inches of organic mulch, which encourages the development of the shallow feeder roots that permit the plants to take up nutrients in the top layer of soil.
In July, when plants are busy developing flowers and young fruits, gardeners should apply an additional dressing of balanced organic fertilizer, with a ratio of four parts nitrogen, six parts phosphorus, and six parts potash. Eggplants require moderate amounts of moisture during the growing season, equivalent to an inch of rain per week.
Control Eggplant Insect Pests
Flea beetles are leaf chewing pests that resemble fleas in size and mobility. The many tiny holes these pests leave weaken the host plant, reducing productivity and eventually causing plant death. Gardeners can fight the adult insects with organic neem spray, and an application of parasitic nematodes can control the larval stage.
Colorado potato beetles are fingernail-sized insects with black and pale yellow bands. Gardeners can look for and crush the orange egg masses under leaves early in the growing season. Floating row covers also exclude the pests from eggplants.
Control Eggplant Diseases
The primary disease concern of eggplants is verticillium wilt. Gardeners can identify this fungal disease by wilting, yellowing, and necrosis at the leaf tips of affected plants.
The best way to control verticillium outbreaks is by following a lengthy crop rotation schedule of five to seven years in the garden. This means that gardeners should not only avoid replanting eggplant in the same site for that duration, but they should also avoid planting tomatoes and potatoes in that site during a five-year period. Good garden sanitation also controls fungal outbreaks, so gardeners should remove all crop residue from the garden at the end of the growing season, and keep diseased plants out of the compost bin.