Kohlrabi can be an intimidating vegetable if you haven’t been around it much. It looks like a leafy, green space alien, and has a taste like fresh, crunchy broccoli stems, with a hint of radish.
The name kohlrabi comes from the German words kohl, meaning cabbage, and rabi, meaning turnip—and that kind of says it all about this delicious vegetable.
Although these green bulbs look like they were dug up from the earth, kohlrabi is actually a swollen stem that grows above ground. Kohlrabi—or “rabi” for the hip, urban foodie set—is widely used in Central Europe and Asia, but I think the time has finally come for this yummy little Sputnik to land in the United States!
Kohlrabi Culture and Cultivation
The kohlrabi plant is easy to grow, has few pests or disease problems, and grows pretty quickly in cool weather. It makes an excellent, relatively care-free substitute for turnips. There are a few different varieties of kohlrabi, and they come in pale green and bright purple, making quite a show in the garden.
When growing from seeds, sow outdoors as soon as the soil can be worked in the spring. If you are in a warmer climate, you may want to start your seedlings indoors, and transplant them out a couple of weeks before the last spring frost. If you start them inside, wait until the baby plants are four to six weeks old before transplanting.
Kohlrabi prefers cool weather, and will lose flavor quickly in the heat, so often people will sow kohlrabi into the garden in the fall, four to six weeks before the first frost, so their plants will mature and sweeten in the cold. Kohlrabi are often the longest lasting vegetable in the garden in the fall, doing very well in cold frames, and even tolerating a nip of snow!
First fertilize your soil with compost or a good organic fertilizer, and then plant your kohlrabi into full sun. You can have a continuous crop if you sow new kohlrabi seeds into the garden every two to three weeks.
Plant the seeds ¼ to ½ inch deep into the soil, about three to five inches apart, then thin to six to eight inches apart as they grow. Also, when growing kohlrabi, you want to keep the soil well watered or you will end up with woody plants that are too tough.
Harvest kohlrabi when the first stem is 1-2 inches in diameter. This takes between 40 and 60 days, depending on the variety of kohlrabi you are growing.
Kohlrabi can be continuously harvested until the stems are two to three inches in diameter. After that, your plants will be too old and too tough.