Kohlrabi is an interesting looking, and easy to grow vegetable. As a child, I remember my grandfather slicing the cool-season vegetable into slices, squeezing a bit of lemon and a sprinkle of salt. The grandkids would swarm him for a slice before we ran off chasing one another through the citrus groves he owned. Growing kohlrabi from seeds can be a fun and rewarding experience.
With just a few steps and a bit of patience, you can easily grow your own kohlrabi in your garden or in containers.
In this blog post, we’ll show you how to grow kohlrabi from seeds in. You’ll learn how to properly prepare the soil for planting, the best time to sow the seeds, and how to care for the kohlrabi as it grows.
So let’s get started and find out how you can easily grow kohlrabi from seeds.
About Kohlrabi
It is a biennial, with the bulb-shaped stem growing in the first year and the plant flowering and producing seeds in the second year.
The taste of kohlrabi is milder than a turnip or even broccoli. Its texture is similar to that of an apple, and it can be eaten raw or cooked.
When to Plant Kohlrabi
I have tried all these methods and I found that winter sowing seeds is the best method. Seeds germinated with very little effort and did extraordinarily well when transferred to their spots.
We set them outside around February and have seedlings ready to plant by April. This is an excellent way to get a jump start on the season.
If you are starting them indoors, plant your kohlrabi seeds four to six weeks before the last expected frost of spring.
If you’re planting in the fall, wait until at least two weeks after the first expected frost of autumn.
Kohlrabi seeds can also be directly sown once the soil has warmed up a bit.
This vegetable does not like hot summer temperatures; however, so if you’re planning to grow kohlrabi during the summer, opt for a variety that matures quickly in just six weeks.
How to Plant Kohlrabi Seeds
As soon as they sprout, thin out any overcrowded seedlings to 3-4 inches apart.
Mulch around the plants to help retain moisture and keep weeds at bay. In cooler climates, it is also recommended to provide a light layer of row cover over the plants for additional frost protection.
Fertilize Your Kohlrabi Plants
Kohlrabi plants need to be fertilized in order to reach their full growth potential.
The best time to fertilize is when the plants are actively growing, usually in early-summer.
A balanced fertilizer should be used. Depending on the growing area, you will want to fertilize accordingly. Read the packaging to ensure you are using the correct amount of fertilizer.
After applying the fertilizer, it is important to water the plants thoroughly. This will help ensure that the nutrients are absorbed by the soil and taken up by the kohlrabi plants.
Kohlrabi can be directly sown or started indoors.
Beautiful kohlrabi plants harvested for a salad.
Varieties to Plant
It can be grown as either a spring or fall crop, but can become stressed in hot summer temperatures.
The fast-maturing variety will be ready to harvest in as little as 6 weeks, making it a great option for the time-pressed gardener. In addition, it’s generally pest-free, so you won’t need to worry about infestations.
When choosing a variety, it’s important to consider the size of your garden. In general, kohlrabi does not need a lot of space. They can be grown in containers or raised beds.
If you have a small space, look for a compact variety like ‘Kolibri’ or ‘Konan’, both of which will only grow to be about 6 inches tall.
For larger gardens, varieties like ‘Grand Duke’ and ‘Superschmelz’ may be better options since they can reach heights of up to 12 inches.
Companion Planting
All vegetables can benefit from companion planting and kohlrabi is no different!
Some common pests to kholrabi are:
Cabbage maggots: These pests feed on the roots of young kohlrabi plants, which can lead to stunted growth and wilting.
Aphids: These tiny insects can cluster on the leaves and stems of kohlrabi, sucking sap from the plant and potentially spreading disease.
Cabbage loopers: These caterpillars can feed on the leaves of kohlrabi, causing large holes and reducing the overall plant health.
Flea beetles: These small, black beetles can chew small holes in the leaves of kohlrabi, which can stunt growth and increase susceptibility to disease.
Slugs and snails: These pests can eat large holes in the leaves of kohlrabi, which can stunt growth and make the plant more vulnerable to other pests and diseases.
For best results, kohlrabi should be planted next to:
Beets: Beets are a good companion plant for kohlrabi as they do not compete for the same nutrients in the soil and help deter pests such as leaf miners.
Onions: Onions help to deter pests like cabbage worms and aphids that commonly attack kohlrabi.
Nasturtiums: Nasturtiums can help to repel aphids, squash bugs, and whiteflies, which can also affect kohlrabi.
Lettuce: Lettuce and other leafy greens like spinach and arugula make good companion plants for kohlrabi as they help to shade the soil and retain moisture.
Chamomile: Chamomile can attract beneficial insects like hoverflies and parasitic wasps that prey on pests like aphids and caterpillars.
How to Harvest Kohlrabi
Kohlrabi can be harvested once it has grown to the size of a tennis ball. You do not want to let it grow too much bigger than this size because it will develop a tough, woody texture.
Once your plant has matured, cut it at the bottom of the roots with a sharp knife. The leaves of the plant make an excellent substitute for spinach and can be eaten in stir-fries, fed to chickens, or composted.
The bulb of the plant is the prized possession. Make sure to peel the skin, and the bulb can be eaten raw or used in cooking. It is absolutely delicious roasted, made into slaw, added to stir-fries, or eaten raw.
Kohlrabi can be stored in the refrigerator for up to four weeks once harvested.
