How to Grow Kohlrabi

By Steven Biggs

Growing Kohlrabi in Home Gardens

THREE CHEERS for one of the most photogenic veggies out there.

To my kids, kohlrabi looked like flying saucers. When I look at kohlrabi from the right angle I see a person having a bad hair day.

Whatever your imagination paints it as, it’s both attractive and unusual, making it a nice fit for an ornamental edible garden.

It’s also easy to grow, quick to mature, and versatile in the kitchen.

If you haven’t tasted it before, I’d describe the flavour as a cross between a mild apple and mild turnip. Let’s call it turnip light!

In this post I’ll talk about how to grow kohlrabi and how to fit it into your garden.

It Starts as a Rosette

Kohlrabi is a member of the cabbage clan. It has an edible stem that fattens up right above the soil level. Before the stem plumps up, though, the plant is a rosette of leaves. As the stem thickens, the symmetry of that rosette remains, with leaves projecting out from the bulb-like stem.

Top Tip for Kohlrabi Success

Here’s the key to your kohlrabi success: Fast, uninterrupted growth.

To get that type of growth, grow the plant in well-fed soil, with cool temperatures and consistent moisture.

Site

How to grow kohlrabi

Kohlrabi is an easy-to-grow vegetable that is versatile in the kitchen.

  • Like its cabbage cousins, kohlrabi grows best in soil with lots of organic matter

  • A spot with full sun is best (although I’ve had decent results growing kohlrabi in partial shade)

Grow Kohlrabi from Seed

Kohlrabi is easy to grow from seed, indoors or outdoors. I don’t usually bother starting them indoors in the spring, but it’s an option if you want the earliest possible harvest. If you start them indoors, there’s no need for a heat mat.

  • Sow seeds approximately 5 mm (1/4”) deep

  • Outdoors: Start sowing about 1 month before the last spring frost

  • Indoors: Start kohlrabi transplants about 1 month before you plant to move them to the garden

Here are a couple of ways to get a longer kohlrabi harvest:

  • Start additional seeds every 2-3 weeks

  • Grow more than one variety, choosing varieties that take different amounts of time to mature

A young kohlrabi plant

A young kohlrabi plant, before the stem has started to fatten up.

Note: While kohlrabi plants are tolerant of cold weather, a hard freeze can cause young plants to bolt – to jump right to the flowering stage. That would mean no thick edible stem. So there’s a limit to how early you can plant them out.

Kohlrabi as a Summer Succession Crop

When kohlrabi is a succession crop, I like to pre-start seedlings indoors (or outdoors, in another part of the garden). That way, I have transplants ready to go once the desired space opens up.

While I rarely start spring kohlrabi indoors in the spring, I find it’s the best way for me to grow kohlrabi for summer succession because:

  • It allows me to have a tighter succession...with larger plants ready as soon as the space is open

  • The hot, dry summer weather that I get here is not ideal for outdoor seeding

Note: Depending on growing conditions in your area – and how much attention you give your garden over the summer – kohlrabi might or might not be a suitable summer succession crop. Dry conditions can cause erratic growth and give a woody texture with a strong, bitter flavour.

Grow a Container Vegetable Garden

And get an early harvest of crops that usually take too long!

Spacing

kohlrabi plant spacing of about 10-15 cm

Thin kohlrabi plants to give a spacing of approximately 10-15 cm (4-6”) apart.

With direct-seeded kohlrabi, I usually plant them more densely than recommended. Then I thin out the row as the stems begin to fatten, enjoying an early harvest of young kohlrabi.

Kohlrabi leaves are edible, so if I thin out any plants before the stems enlarge, I can still add the leaves to a salad!

Planting more densely is also cheap insurance against losses and poor germination.

For large kohlrabi, select a variety known for size

If you’re aiming to grow larger kohlrabi, increase the spacing a bit – and look for a variety know for size.

  • Sow the seeds approximately 5 cm (2“) apart

  • Thin to 10 – 15 cm (4-6”) apart

  • Space rows 30cm (12”) apart

If you’re aiming to grow larger kohlrabi, increase the spacing a bit – and look for a variety know for size.

Challenges

I find the early crop is not bothered much by pests. But later sowings and summer-succession transplants are growing when there are more pest pressures in the garden. That means young seedlings can be vulnerable to flea beetles, cabbage worm, and cabbage looper. An easy solution is to cover young plants with a floating row cover.

Where possible, rotate crops to minimize pest and disease pressures. That means it’s best not to plant kohlrabi where you’ve had you’ve had related crops (broccoli, cauliflower, collards, kale, turnip, rutabaga, cabbage, bok choy, Brussels sprouts, and mustards) in last 4 years.

Harvest and Storage

Kohlrabi usually take a couple of months to mature. Pick when they’re anywhere between the size of a golf ball and a tennis balls. Remember: smaller will be more tender.

Kohlrabi is frost hardy, so there is no rush to harvest it in the fall.

In the Kitchen

Using kohlrabi in the kitchen

Kohlrabi is versatile in the kitchen.

You can eat kohlrabi raw or cooked. Either way, peel it first, because the skin can be tough. I prefer to use a paring knife (sometimes a potato peeler gets stuck on the spots where the leaf joined the stem.)

Here are some ways I’ve enjoyed serving kohlrabi:

  • Sliced, on a veggie platter

  • Grated, in slaws and salads

  • Poached (in white wine with butter is nice!)

  • Cut into ribbons, and added to a stir fry

  • Cubed and added to curries

Remember: The young leaves and leaf stalks are edible too!

Find This Helpful?

Enjoy not being bombarded by annoying ads?

Appreciate the absence of junky affiliate links for products you don’t need?

It’s because we’re reader supported.

If we’ve helped in your food-gardening journey, we’re glad of support. You can high-five us below. Any amount welcome!

About the Author – Steven Biggs

Bored of rows? Try a patchwork of lettuce. A focal point of edible flowers. A perennial bed edged with edible plants. When it comes to irresistible food gardens, horticulturist Steven Biggs sees the whole yard as a canvas—with a palette of veg, fruit, herbs, and edible flowers. With over 25 years in the horticulture sector, he’s worked as a college instructor, in greenhouse and nursery production, plant propagation, biological controls, and horticultural supplies. But his passion is to help people get creative with their home gardens. To think outside the box. To tailor the garden to what they love. That might be intrigue, form, texture, unusual ingredients, or a long harvest window. Maybe it’s as a creative outlet. If he’s not in his garden, you’ll catch him recording his award-winning Food Garden Life podcast, writing gardening books and articles, and helping home gardeners think outside the box in one of his online classes.


More Articles       Courses       Free Food-Gardening Guide       Donate
Previous
Previous

Grow Vegetables in Straw Bales

Next
Next

Ornamental Vegetables for Fall