Kohlrabi is a cabbage vegetable that can be successfully grown in your own backyard. Here's everything you need to know about planting kohlrabi.
Kohlrabi (Brassica oleracea var. gongylodes L.) is a member of the cabbage family that is very rich in vitamins and nutrients. In contrast to many other types of cabbage, it is not the inflorescences (such as cauliflower and broccoli) that are harvested from kohlrabi, but the stems that are thicker at the bottom. In its cultivation, the kohlrabi also differs somewhat from its peers. In this article you will find out what you should consider when planting kohlrabi and which varieties are particularly tasty!
Growing kohlrabi: location and the right season
Kohlrabi is a relatively fast-growing culture. The cultivation period is between 10 and 14 weeks. Depending on whether you want to grow your kohlrabi yourself or prefer to use seedlings from a specialist retailer, the optimal time to plant kohlrabi may vary.
Planting kohlrabi: the right location
Kohlrabi is a very fast-growing vegetable that does not have the highest demands on its location due to the short cultivation period. The taste of kohlrabi mainly depends on the consistency of the tubers. The faster they grow, the softer the tuber tissue will be later. In order to guarantee rapid growth, compost (and, if necessary, well-rotted manure) should be worked into the bed as early as autumn. The bed prepared in this way can then lie fallow over the winter and wait for the kohlrabi plants. The lighting conditions should be semi-shady to sunny so that the growth of the tubers is not impaired. Alternatively, you can also work a primarily organic long-term organic fertilizer such as our Plantura organic tomato fertilizer into the soil before planting. This is how you create optimal conditions for strengthened kohlrabi plants.
Plant kohlrabi
The kohlrabi plants are ready to be planted out at the end of March/beginning of April. Planting distances of 25 to 50 cm should be chosen, depending on the variety, so that the plants don't compete too much for light and water.
Important: Plant the kohlrabiPlant seedlings only 2 to 4 cm deep. This prevents the tuber from having direct contact with the ground and possibly rotting! The soil should be watered regularly during the 10 to 14 week growing season to avoid stagnation in growth.
Warning: Waterlogging should be avoided at all costs. Otherwise the tubers that grow above ground tend to burst and rot!
Here is a summary of the most important steps:
- Loosen the bed before winter, enrich it with humus and leave it fallow.
- Grow seedlings in the greenhouse or windowsill for about 6 weeks.
- Plant kohlrabi: 2 to 4 centimeters deep; no earlier than the end of March; Maintain row spacing of 25 to 50 cm (depending on the vigor of the variety).
- Water regularly, but avoid waterlogging!
Planting kohlrabi on the balcony
If you don't have access to a bed, but have a beautiful and sunny balcony, you don't have to despair. Kohlrabi cultivation is also successful there. However, the absolutely necessary distances of at least 25 cm between the individual kohlrabi plants are a limiting factor. Usually the plant pots are only big enough to accommodate a kohlrabi plant.
Tip: A self-made raised bed can serve as an alternative to the plant pots. You can find instructions on how to build your own raised bed here.
Growing kohlrabi: Grow it yourself or buy kohlrabi plants?
Buy Kohlrabi Seeds
Kohlrabi seeds are available in every well-stocked specialist shop and from many garden mail order companies. A packet of seeds with around 50 seeds can be bought for as little as 1.30 euros. First, the seeds are grown in small pots (diameter approx. 5-6 cm) or on pot trays. It is important to use a loose and water-bearing planting medium (such as compost). During the germination phase, kohlrabi needs temperatures of around 20°C. These temperatures are best reached on the windowsill or in the greenhouse. After the kohlrabi has germinated, the temperature can be reduced.
Caution: However, it should not fall below 10°C, otherwise tubers may not appear educated! The kohlrabi should not be planted before the end of March to avoid night frosts.
Buy kohlrabi plants
The safestAnother way to get he althy and strong young plants is to buy kohlrabi seedlings from specialist retailers. The young pupils are often sold on multiplates with 10 or more plants. The seedlings are also very affordable. For only two euros, you can buy a pot tray with around 10 young plants. At the time of purchase, the plants have mostly left the greenhouse phase and are 6 to 8 weeks old.
Kohlrabi Varieties: 'Super Schmelz' and other Kohlrabi Varieties
There areKohlrabi - like almost all members of the Brassicaen (cruciferous plants) - in many different varieties. The primary distinction is between white and blue kohlrabi. The most well-known variety is 'Super Schmelz', but there are many other interesting variations. We have put together a selection of the best kohlrabi varieties for your garden:
- Super Schmelz: Tried and tested white variety; no lignification, therefore very tender; high yield; large tubers (up to 5 kg possible).
- Blaro: purple variety; known for its delicate flavor; does not tend to bolt.
- Knaufs Frühweiß: Old, traditional variety; known for good aroma; very early ripe; light green, flat tubers.
- Giant: Very slow growing variety; can reach tuber weights of up to 5.5 kg; Note the time of harvest as there is a tendency to woodiness.
- Azurstar: Fast-growing variety; early harvest time; purple tubers.
Read more about the variety of kohlrabi here.
Harvest Kohlrabi: When is harvest time?
The harvest period for kohlrabi cannot be narrowed down so easily, as it can be planted from early spring to mid-summer. Rather, there are some distinctive signs to watch out for so you can harvest your beloved kohlrabi at the right time. We have listed some tips for you:
- Rule of thumb: The kohlrabi tubers are ready for harvest about 12 weeks after planting out (subject to differences depending on the variety)
- Aboveground tuber is flat round/oval
- Blue varieties take longer to ripen than white kohlrabi varieties
- Leaves are juicy green
- White varieties are more prone to woody growth than blue ones
- Harvest kohlrabi before the first winter frost at the latest
- Don't wait too long: tissue becomes lignified as it growsPlantage
Conclusion: It is better to harvest your kohlrabi a little too early than too late. The possibly slightly lower yield is compensated by the finely spicy taste and the better consistency!
Storing and preserving kohlrabi
- Store kohlrabi in the fridge
Kohlrabi will keep in the fridge for about a week. You should first remove the woody parts and leaves to reduce the evaporation surface. - Freezing kohlrabi
Kohlrabi can also be stored frozen. Wash and portion your kohlrabi beforehand and blanch them in boiling s alted water for 2 to 3 minutes. Less of the juicy green is then lost during thawing. - Preserving kohlrabi
Before you can preserve your kohlrabi, you should blanch it for a few minutes. After blanching, place the kohlrabi in mason jars. You can now fill the glasses with s alt water or a delicious vegetable sauce.
Important: Whether s alt water or sauce, both liquids should be boiled and cooled before pouring into the glasses! This ensures a longer shelf life. After sealing the jars, they should be boiled again for about 20 to 30 minutes.
"For more information on storing kohlrabi, see this article.