Kohlrabi is a unique and lovely addition to any vegetable garden, with its colorful swollen stem and rosette of blue-green leaves.
Although kohlrabi tolerates some heat, planting should be timed for harvesting during cool weather. Kohlrabi has a shorter growing season than cabbage and grows best in cool weather. If your area has cold winters, plant for summer to early fall harvest. In the South, plant for harvest in late fall or early winter. With spring plantings, start kohlrabi early so that most growth will occur before the weather gets too hot.
Kohlrabi is usually grown from transplants started indoors, but you can sow seed directly in the garden. Plant the seeds 1/4 to 1/2 inch deep; thin them to 5 to 6 inches when they're large enough to handle. Kohlrabi likes fertile, well-drained soil with a pH between 6.5 and 7.5. The soil should be high in organic matter. Kohlrabi should have even moisture so it doesn't become woody.
When the swollen stem enlarges to 2 to 3 inches in diameter, harvest kohlrabi by cutting at ground level.
Although the varieties of kohlrabi feature different colors, all edible parts are the same pale yellow. We've listed the types of kohlrabi below.
- Grand Duke, harvest at 45 days, is an All America Selection.
- Early White Vienna, harvest at 55 days, is a commonly grown, light green variety.
- Early Purple Vienna, harvest at 60 days, is a light purple form.