Japanese eggplant is a long, slender member of the nightshade family that has the same taste and texture as the larger eggplant used in dishes like eggplant parmigiana. The eggplant became popular in the United States in 1806 when Thomas Jefferson introduced them. Related to tomatoes and peppers, they are often grown as a summertime annual vegetable and used in Asian stir-fry dishes and tempura. If you like the larger, plump eggplant, you’ll like Japanese eggplant, too. And it’s as easy to grow as its cousin the tomato.
Start Japanese eggplant seeds indoors at least six weeks before your final spring frost. Fill a nursery flat with a light potting soil and make half-inch deep holes 2 inches apart. Insert one seed into each hole and cover the holes with soil.
Keep the flat well watered and in an area that receives full sun. You might need to provide artificial light—a standard fluorescent shop light will do the job if you hang it 4 to 6 inches above your flat. Keep it on for about 12 hours a day and raise it as your seedlings grow.
Prepare your garden soil for the eggplants by digging in compost and peat moss. For every 6-foot row, dig in about 2 gallons of compost and half that amount of peat moss. Dig holes large enough for your eggplants’ roots, and make them about 12 inches apart if you are planting more than one Japanese eggplant.
Transplant your Japanese eggplant seedlings to the garden when they are about 6 inches tall. Be sure to wait until after your final spring frost, because this plant is frost tender.
Keep your eggplant well watered and fertilize it with a balanced plant food designed for tomatoes or other vegetables once a month, but stop fertilizing in mid-August.
Spray plants with insecticidal soap if you notice aphids, scale insects, lace bugs or spider mites. Spray every other day after the sun has left your garden to avoid sunburn. Protect them from slugs and snails by scattering iron phosphate granules on the soil around your plants.
Harvest your Japanese eggplants while they are young and tender. Picking the fruit also encourages the plant to produce more flowers and fruit.