How to Grow Kohlrabi from Seed to Harvest
You plan to grow kohlrabi in your garden or on your balcony? Good news! It’s fairly simple and can also be quite a lot of fun.
However, before you start, make sure to read this article since I explain all the steps you need to take to grow kohlrabi from seed to harvest in the best possible manner.
I also included some video material from other gardeners to make this article the most comprehensive one when it comes to growing kohlrabi at home.
Without further ado, let’s get right into it! 😉
Table of Contents
Kohlrabi Plant Profile
|Size||7 to 10 inches tall and 6 to 9 inches wide.|
|Climate||Kohlrabi grows best in cool to moderate climatic zones with optimal temperatures between 50 and 70 degrees Fahrenheit.|
|Sun Exposure||Kohlrabi grows best with full sun.|
|Soil Requirements||Kohlrabi plants grow best in acidic soil with optimal pH between 5.5 and 6.5.|
|Country of Origin||Northern Europe.|
|Growing Difficulty||Easy – Intermediate. You don’t need to be an expert to grow kohlrabi, yet you should still comply with the advice in this article to make your kohlrabi growing project a success.|
|Perennial?||No, kohlrabi is harvested in the first year.|
|When should you start?||Between mid of March and the end of May, depending on the region you live in.|
|Expected Yield & Harvest||One kohlrabi head per plant and it will take between 60 and 80 days to grow kohlrabi from seed to harvest.|
|What to do with it?||You can just eat kohlrabi raw or make salads or casseroles out of it.|
What Types and Varieties of Kohlrabi can you grow?
There are several different kohlrabi varieties you can grow at home. I listed the most popular ones for you below:
- Early White Delicacy
While I love to grow Kolibri kohlrabi due to its interesting color and its decent yields, I suggest you just try out many different kohlrabi varieties so that you get a better feeling for what varieties you like most.
In fact, by planting many different kohlrabi varieties, you can select your favorite ones that you can also grow for future years.
Moreover, growing various different kohlrabi varieties can also be quite a lot of fun since it can be quite interesting to see all the different shapes and colors of your kohlrabies.
Consequently, just pick a handful of different kohlrabi varieties and you are good to go. You can also just use a kohlrabi seed mix if you are the adventurous type of person and love surprises 😉.
When should you start to grow Kohlrabi?
The best time to start growing kohlrabi is usually between mid of March and the end of May.
However, please note that this is only a rough indication and that the optimal start date to grow your kohlrabies also depends on the overall climatic conditions in your region.
For instance, while you can start with your kohlrabi growing project earlier in hotter climatic zones, you will have to wait longer in colder climatic zones.
In general, I advise you to start growing kohlrabies around one month before you expect the last freeze of the season.
Of course, this is only true if you grow your kohlrabi seedlings indoors and transplant them outdoors later on in the year.
If you want to directly start outdoors, make sure to wait until temperatures no longer drop below the freezing mark.
How long does it take to grow Kohlrabi from Seed to Harvest?
It will usually take between 60 and 80 days to grow kohlrabi from seed to harvest.
However, please note that this depends on several factors, including the climatic zone you grow your kohlrabi, the soil conditions, how much sun your kohlrabi plants get and also your individual skill level.
In fact, if you are still a beginner and haven’t grown kohlrabi before, you can expect that it will take you longer to grow kohlrabies compared to a gardening expert who knows exactly what he’s doing.
However, don’t see longer growing times as a bad thing. The longer it takes you to grow kohlrabies, the longer you can enjoy the growing experience.
Hence, just enjoy the ride instead of just the harvest and you will not care if it takes a few days more or less to grow your kohlrabies from seed to harvest.
What is the best Climate to grow Kohlrabi?
Kohlrabi plants grow best in cool to moderate climatic zones. However, this doesn’t mean that you cannot grow kohlrabi in warmer climatic zones of our planet.
It just means that kohlrabi likes rather cool temperatures and if you live in warmer climatic zones, you should start out pretty early on in the year so that your kohlrabies can develop in an optimal manner.
What Temperatures do Kohlrabi like?
Kohlrabi plants usually grow best in the temperature range between 50 and 70 degrees Fahrenheit. Yet, please note that we are talking about optimal conditions.
In fact, seed companies did a great job over the past decades to develop kohlrabi strains that are quite resistant to outside temperatures.
Hence, even if you are not able to provide this optimal temperature range for your kohlrabi plants, don’t get discouraged.
As long as you live in regions with rather moderate climatic conditions, you will just be fine most of the time.
What do you need to grow Kohlrabi?
You don’t need a lot of equipment to grow kohlrabies. However, there are still some things I advise you to get so that you can enjoy your kohlrabi growing project in an optimal manner.
- Growing bed (to grow your kohlrabi seedlings, only necessary if you don’t plant kohlrabi directly outside)
- Flower pots (only necessary if you don’t have a garden to grow your kohlrabies)
- Kohlrabi seeds
- Fertilizer (you can make your own organic fertilizer for which I give you the instructions below)
- Potting soil
- Slug fence
- Watering can
- Garden shovel
- Compost (optional)
- Motivation for growing kohlrabi 😉
What Yield can you expect when you grow Kohlrabi?
Most kohlrabi varieties only produce one crop per plant. However, since those crops can reach a quite decent size, this will not be a problem.
In fact, kohlrabies don’t need plenty of space to grow and you can plant many kohlrabi plants in your garden to produce significant kohlrabi yields.
What should you grow with Kohlrabi?
If you want to learn about what plants you should grow next to kohlrabis, make sure to check out my article that shows you the best and worst kohlrabi companion plants.
Why should you grow your own Kohlrabi?
There are many reasons to grow kohlrabi plants at home. Yet, it will take more effort and may also be more expensive compared to just getting your kohlrabi from the store.
However, there are several benefits of growing kohlrabi at home. For instance, growing kohlrabi can be quite a lot of fun.
In fact, I love growing my own plants and see them progress every week. It is just nice to see how plants develop from just a small seed into such big plants and I am really fascinated about it.
Moreover, growing kohlrabies in your garden or on your balcony can also greatly reduce your overall stress level.
If you work in a demanding job for long hours, you sometimes need a break and just unplug from your stressful daily life.
Growing kohlrabi is a great way to do so since it can slow down your stressful life quite a lot.
Of course, this is not only true for growing kohlrabi, but for gardening at home in general.
Additionally, growing kohlrabi can also bring you back to the roots.
What I mean by this is that our ancestors have grown their own plants for many thousands of years at home and you can follow this noble tradition to reconnect to nature.
Finally, growing kohlrabi at home can also have significant positive effects on your health.
In fact, by growing kohlrabi yourself, you do no longer have to rely on kohlrabi from the store.
In conventional agriculture, plenty of chemical pesticides and herbicides are used and part of those substances will also end up on the kohlrabies you buy in the store, which can be quite harmful to our health in the long run.
Hence, you can also do your health a favor by growing your own kohlrabies since you don’t have to use any chemical substances and can grow your kohlrabies in a fully organic manner.
Growing Kohlrabi: Step-by-Step
1. Select a Site for your Kohlrabies
After I hopefully convinced you that growing your own kohlrabies at home is indeed a good idea, let’s get into the actual planning phase for your kohlrabi growing project.
First of all, you have to figure out the perfect site for growing your kohlrabies. I answer various questions for you regarding this topic in the following chapters.
Does Kohlrabi like Sun or Shade?
Yes, kohlrabi plans like full sun. In fact, the more sun they get, the better they will grow.
Of course, I know that most people will not have the opportunity to provide their kohlrabi plants with sun all day long and this is not a problem at all.
Just make sure to choose the sunniest spot possible in your garden or on your balcony and you are good to go.
What are the Soil Requirements of Kohlrabi?
The optimal soil pH for growing kohlrabies is between 5.5 and 6.5, meaning that kohlrabi prefers a slightly acidic environment to grow in an optimal manner.
While this may sound complicated at first, it is actually not complicated at all and you can meet those soil requirements by just getting some potting soil from your local garden center.
You can also mix your potting soil from the store with soil from your garden and you can also add some compost. By doing so, you can provide optimal soil conditions for your kohlrabi plants.
How much Space do Kohlrabi Plants need?
Since kohlrabies stay rather small and compact, they will not need too much space.
You should provide each kohlrabi plant with at least 4 square feet of space so that they can grow in an optimal manner and don’t have to compete for sunlight or nutrients with each other.
Of course, if space is no problem for you and you have a pretty big garden, feel free to offer your kohlrabies much more space.
In fact, the more space you offer to your plants, the better they will grow.
Should you plant Kohlrabi in a Pot or in your Garden?
If you have a garden, I highly recommend you plant your kohlrabies in your garden instead of growing them in a pot.
Your kohlrabies will just have much more space in your garden compared to a pot and they will also have more natural growing conditions.
Of course, if you don’t have a garden and live in a flat where you just have a balcony, you will have no other choice than to grow your kohlrabies in pots on your balcony.
2. Plant Kohlrabi Seeds
After you figured out the optimal location for your kohlrabi plants, it is time to go into detail regarding the actual kohlrabi seeding process.
Should you buy Kohlrabi Seeds or Seedlings?
First of all, you have to decide if you want to grow kohlrabies from seedlings or seeds.
While it is possible to get kohlrabi seedlings from your local garden center, I would not advise you to do so but to grow your own kohlrabi seedlings instead.
The reason for this is that you will only get the full kohlrabi growing experience if you grow your kohlrabies from seed to harvest.
In fact, growing your own kohlrabi seedlings is the first important step in the whole growth project and especially if you have never produced your own seedlings, you should definitely go for it.
And don’t be intimidated. Growing your own kohlrabi seedlings is pretty simple and I show you how to do it step-by-step in the following chapters.
Should you buy Kohlrabi Seeds or produce Seeds by yourself?
Now that I hopefully convinced you that you should grow your own kohlrabi seedlings, you still have to get your seeds from a vendor.
While I often advise you to produce your own seeds for your growing projects, it will simply not be possible to do so if you have never grown kohlrabi before since kohlrabi seeds are extracted from flowers and cannot be harvested from the crop itself.
Hence, just get kohlrabi seeds from a seed company for your first kohlrabi growing project and you are good to go.
How to plant Kohlrabi Seeds
Now that you got your kohlrabi seeds, it is time to go into the actual seedling process.
You can either plant your seeds directly outdoors into your garden or you can raise kohlrabi seedlings inside your four walls and transplant them later on.
I prefer the second option since kohlrabi seedlings will be much safer indoors and you can also start earlier on in the year with your growth project.
If you start indoors, just fill your growing bed with soil and place your kohlrabi seeds onto the soil surface.
Make sure that you leave at least 3 inches between your seeds into each direction so that your kohlrabi seedlings get enough sunlight and nutrients to develop in a proper manner.
After you placed your seeds, cover them with an additional one-inch soil layer. Finally, water your growing bed and place it in a bright spot in your home.
Make sure to plant more seeds than you want to get seedlings since not all seeds will germinate.
A good rule of thumb is to plant 2 seeds for every seedling you want to get.
How long does it take to see the first Kohlrabi Seedlings?
After about one week, you should see the first seedlings.
However, please note that this can also take a little bit longer, depending on the overall conditions inside your home and also on how deep you actually planted your seeds into the soil.
Hence, just be patient and you will see results sooner or later.
However, after just one month, it is time to evaluate the situation a little bit more critically.
If you haven’t grown enough kohlrabi seedlings by now, it is time to plant some additional seeds.
How to protect your Kohlrabi Seedlings indoors
During the time your kohlrabi seedlings stay indoors, you don’t have to worry about any additional protection measures.
In fact, your kohlrabi seedlings will do fairly well in your growing bed and you don’t have to worry about any manual actions yet.
However, if you have pets, make sure that they will not have access to your growing bed in order to avoid any unpleasant surprises for your kohlrabi seedlings.
When should you transplant your Kohlrabi Seedlings?
After your kohlrabi plants had several weeks to grow in your growing bed, it will be time to transplant them outdoors sooner or later.
But when should you actually transplant your kohlrabi seedlings outdoors?
Well, for me, two main criteria have to be met before I do so.
First, you should make sure that your kohlrabi plants have a minimum height of at least 4 inches.
Only then will they be resistant enough to deal with the harsh outside conditions.
Second, you should also make sure that the overall climatic conditions are right to transplant your kohlrabi plants outdoors.
Climatic conditions are right if you don’t expect any freeze anymore during the growth period.
In most moderate climatic zones of our plant, this should be between mid and the end of May.
If both criteria are fulfilled, you first have to prepare your growing site before actually transplanting your kohlrabi seedlings.
Just dig one hole for each seedling into your garden.
The hole should be at least 4 square feet in size and should be around one foot deep. After that, mix the potting soil from the store with the soil from your garden.
If you engage in composting, you can also add some compost to the soil mix.
Make sure that you loosen up your soil mix a little bit and fill up your holes with the soil.
After that, just transplant each kohlrabi seedlings onto each spot and you are good to go. Finally, just water your seedlings.
Of course, if you just want to grow your kohlrabies straight in your garden without raising kohlrabi seedlings indoors first, you can jump straight to this chapter and don’t need a growing bed.
However, make sure that you don’t plant your seeds until temperatures no longer drop below the freezing mark.
What kind of Protection do Kohlrabi Seedlings need outdoor?
Compared to the safe indoor environment, your kohlrabi plants will now have to deal with the harsh outdoors reality.
In fact, there are several dangers waiting for your kohlrabi plants outdoors and you have to protect them against snails and other animals if you want to make sure that your kohlrabi seedlings will actually survive.
For protecting your kohlrabi seedlings, just use a slug fence. Slug fences are an easy but yet efficient tool to protect your seedlings.
Make sure not to use any chemical protective measures to protect our local flora and fauna as well as your soil and your health.
3. The Kohlrabi Growth Process
Now that you successfully transplanted your kohlrabi seedlings outdoors, you have already managed the hardest part of your kohlrabi growing project. If you got to this point, congratulations!
I know it takes some work to get there, but I hope you loved the process as I do.
In the following, I give you some additional information regarding the further growth process and what you have to consider.
Should you prune your Kohlrabi Plants?
No, there is no need to prune your kohlrabies. As long as you give your kohlrabi plants enough space so that they get sufficient sunlight and nutrients, there is absolutely no need to prune them and pruning can actually do much more harm than good.
Just let it grow and let nature do its work. You will be surprised how well your kohlrabi plants will do if you don’t interfere with nature too much.
Do you have to pollinate your Kohlrabi Plants by Hand?
No, you don’t have to pollinate your kohlrabi plants by hand. Just let them grow and natural processes will do the work for you.
Should you stake your Kohlrabi Plants?
There is also no need to stake your kohlrabi plants. Kohlrabies stay rather small and compact and there is simply no reason why you should stake them.
Since they will stay quite compact, they will be able to stabilize themselves in a proper manner and no additional manual action from your side will be needed.
4. The Kohlrabi Harvest
You can see how well you followed the instructions in this article when it finally comes to harvesting your kohlrabies.
When should you harvest your Kohlrabi?
You can pick your kohlrabies when they reach the size of a baseball. While some kohlrabi varieties may get a little big bigger, the baseball size gives you a rough estimate of when it is time to actually harvest your kohlrabi crops.
If you are not sure if the time is right, just pick on crop and taste it. If it has the taste you would expect from kohlrabies, you can also harvest your other kohlrabies. If not, just let them grow for a little bit longer.
How to store your Kohlrabi?
Kohlrabi can be store for many weeks if it is stored properly. The best location to store your kohlrabi is in a dark and dry place inside your home.
While you could store kohlrabi for an extensive period of time, I would still suggest that you consume it shortly after you harvested it since kohlrabi will contain the most precious nutrients at this stage and will also taste best right after the harvest.
What should you do with your Kohlrabi?
You can use kohlrabies in various different ways. Why you can just eat them raw, you can make salads or use it for casseroles. Whatever you want to do with your kohlrabies, do it!
After all, you did all the work to grow your kohlrabies from seed to harvest and you should also be the one enjoying the fruits of your labor.
Kohlrabi Plant Care Tips
While I have already shown you all the information your need to know to grow kohlrabies at home step-by-step, I still have to answer some more general questions regarding the kohlrabi growth process in the following.
How often should you irrigate Kohlrabi?
You should irrigate your kohlrabi plants whenever they need it. But when do they actually need water? One indication that your kohlrabi plants need water is when their leaves begin to hang.
In fact, an experienced gardener could often tell just from the overall appearance of their kohlrabi plants if they need water or not.
However, you might not have this level of experience yet. In this case, you can use the following tip. Just dig a small hole with your finger right next to your kohlrabi plant.
Pull your finger out of the soil. If soil sticks to your finger, this means that the soil is still wet enough and that you don’t need to water your kohlrabi plants right now.
Yet, if there is no soil sticking to your finger, this means the soil is pretty dry and you should water your plants soon.
Of course, as time goes by and you become a real expert in growing plants, you will develop a deep intuition regarding when it will be the best time to water your kohlrabies.
Hence, don’t get discouraged if you make some mistakes in this regard during your first year of growing kohlrabies.
It is actually perfectly normal to make mistakes and you should not beat yourself up too much if not everything goes well in the beginning.
At what Time of the Day should you water your Kohlrabi Plants?
The official answer is: You should water your kohlrabi plants in the early morning.
However, please note that is only the answer that many growing experts will give you. The truth is a little bit more complicated.
In fact, in my opinion, it doesn’t matter too much when you actually water your plants and I haven’t seen any difference regarding the time of the day I irrigate my plants.
Of course, you should make your own experiences, but it is much better in my opinion to just water your kohlrabies whenever they need water instead of relying on a fixed time of the day to irrigate your plants.
How often should you fertilize your Kohlrabi Plants?
Since you already provided a healthy soil mix for your kohlrabies if you followed all the instructions in this article, there will be no need to add additional fertilizer during the growth process.
In fact, adding additional fertilizer can even do much more harm than good since it can burn the roots of your kohlrabies.
What kind of Fertilizer should you use for your Kohlrabi Plants?
If you come to the conclusion that adding additional fertilizer is indeed a good idea, at least make sure to rely on natural fertilizer instead of using chemical substances to protect the soil and also our flora and fauna.
While you could just order organic fertilizer from a store, you can also easily make your own organic fertilizer.
Just collect some stinging nettles and put them in a bucket full of cold water (make sure that you wear gloves when collecting stinging nettles).
Just leave your stinging nettles in the water for a few days and remove them afterward.
And here you go. You have created a perfectly natural fertilizer that you can add to your kohlrabies on a regular basis.
Should you use Pesticides or Herbicides for Growing Kohlrabi?
You can not only use the stinging nettle liquid for fertilizing purposes, you can even use it as natural pesticide.
Just spray it onto your kohlrabi plants and you will be surprised how well it will work against many different pests.
Instead of using herbicides, just remove weeds by hand and you are good to go.
If you want to learn more about pest control, also make sure to have a look at how to get rid of kohlrabi diseases and pests.
What’s left to say?
First of all, thanks for reading my article to the end. I know it was a pretty long kohlrabi grower’s guide.
However, I was not able to make it any shorter without leaving out any important information regarding how to grow kohlrabi from seed to harvest in the best possible manner.
I hope you get plenty of value out of this article. If so, make sure to share it with family and friends.
If you want to get even more information on growing kohlrabi, make sure to check out my growing kohlrabi FAQ guide.
And now it’s your turn, stop reading and start growing! 😉
About the author
My name is Andreas and I’m really passionate about our environment and also about growing plants. In fact, I have grown several different plants over many years. I love to see my own plants grow and always try new things.
In my blog posts, I want to share my experiences with you so that you can become successful in growing various different plants, even if you are still a beginner right now.