Growing horseradish in a pot or container is not difficult. I can actually almost promise you that you will be successful. There is however a very good reason why you should grow horseradish in a pot or container.
Why you ask? Horseradish grows and spreads to the extent that it can almost be called invasive.
If you grow horseradish in a vegetable garden the plant will grow and develop side roots. And when you harvest the good roots, you will find that it is next to impossible to remove all the horseradish roots left behind.
And next year you will find that the roots left behind will start to sprout and grow again. Growing in a confined space like a container will however let you control the growth of the plants and the spread of the horseradish roots.
Do you still want to grow your own horseradish this year? Great, me too. And I think you should.
Growing horseradish at home is a great way to save money on store-bought produce and you’ll love the taste of your own fresh homegrown horseradish sauce!
- Horseradish – the delicious and hardy perennial
- How to: Growing horseradish plant in a pot or container
- Preparations when first planting horseradish
- Horseradish roots planted – now what?
- How to care for plants using a store bought root
- How to care for horseradish when using fresh cuttings
- Companion planting
- Propagation of horseradish – how to divide horseradish plants
- Harvesting your horseradish root
- How to store horseradish
- Frequently asked questions
Horseradish – the delicious and hardy perennial
Some plants need love and attention to yield generous crops year after year. Horseradish plants suffer none of those fickle traits.
Actually, it is quite the opposite. The horseradish will spread and grow year after year if you let it. It will quite happily take over your entire vegetable garden should you allow it.
This is also one of the reasons why we recommend that you grow your horseradish in a pot or container.
And even if you decide to move the plant outside you are well advised to keep it in a container without a bottom to control how the plant grows and spreads.
You should be aware that if you decide to grow horseradish in your vegetable garden it may be for life.
What I mean is that the root system can get quite big. And if you do not clear it out completely, the plants will spread through its lateral roots and rhizomes. The horseradish will come back again and again if you let it.
How to: Growing horseradish plant in a pot or container
Horseradish packs quite a strong flavour and a little goes a long way. Having grown up in Scandinavia we actually jokingly referred to the root as the Wasabi of the north.
And since a little goes a long way I have never dedicated large areas for this vegetable.
I do however find that horseradish roots taste the best in their first year of growth.
Consequently I grow fresh horseradish plants every year. And I always use fresh cuttings from last year’s harvest when planting new roots in the spring.
You can absolutely grow and keep the horseradish plants in a pot or container until you harvest the root. But most people do grow it in their vegetable garden as it is quite large.
I personally use planting boxes that I have built from left over wood. But again, any container will do.
The photos show a root cutting that was planted in a pot about 2 months ago (mid-May) and the size of the same plant today. The pot will not be harvested until the first frost kills off the leaves later this year.
I recommend pots that are at least 60cm (25 inches) deep with a similar width across. When selecting your pot or container it is good to remember that horseradish planted in situ should be spaced approximately 50cm (20 inches) apart.
If possible place the pot or container in full sun but the plant will also grow in partial shade.
Preparations when first planting horseradish
When you first get started you of course do not have any plants to harvest cuttings from. One solution is to buy seeds or fresh root cuttings from a specialist store.
But my favourite method is a lot less complicated and more fun. It starts at my local supermarket where I head to the organic vegetable section. If there is a farmers market where you live – even better.
Anyway, back to my supermarket. I choose horseradish roots that look healthy and feel firm and solid – but not hard like a piece of rock. I prefer small roots when I can find them.
I recommend choosing organic horseradish roots to avoid any chemicals added to stop the growth of new roots. These chemicals are sometimes added to keep the horseradish looking neat and presentable.
When I arrive back home I prepare a container with good planting soil and organic compost. Mix together to create a soft well drained soil mixture. The container should be at least twice as deep as the roots you are planting.
Next I create a hole in the soil that will allow planting the horseradish at a 45 degree angle. Make sure to leave roughly 5 centimeters (2 inches) of space to cover the root.
When the hole is prepared I place the root in the hole at a 45 degree angle. Always place roots in the hole with the narrow end or tip down.
I make sure to allow for growing space below the horseradish root. The roots will grow quite aggressively when it gets going.
It is of course important to choose a container with good drainage. The horseradish wants to grow in moist but never soaking wet soil.
Horseradish roots planted – now what?
The planted store bought horseradish will act as the plants taproot. A taproot as you may already know is a root system best described as having a larger, dominant and central root from which other roots and rhizome will sprout.
The difference between roots and rhizomes are that the rhizomes are underground stems and new branches of the plant will grow from these underground stems. The rhizomes actually store food and energy for the plants leaves and roots.
When we harvest our horseradish we will be harvesting the roots that grow from this main root, called the taproot. It is also these new formations – that grow from the taproot – that will be the planting materials for next year’s plants.
The horseradish is quite cold resistant and will come back in the spring even if the ground freezes. It works well to place the container outside when the frost season is over.
For me in the southern part of Scandinavia this is usually in the month of march or april.
How to care for plants using a store bought root
It is quite straightforward to care for horseradish plants.
Horseradish is a hardy perennial but does not like to dry out. To avoid dry outs I mulch with fresh grass clippings to keep the soil and growing environment moist and well nourished.
If you grow horseradish in your vegetable garden you need to allow for plenty of room for it to grow. One plant is usually enough for a family but should you decide to grow more plants I recommend leaving about 1 meter (40 inches) between plants.
Should you decide to keep it in a container, do remember that containers and pots do dry out quicker than when planting in your garden.
If you are just starting out growing horseradish from store bought roots, your first year’s harvest will be focused on the lateral roots growing from the tap root.
Chances are that the store bought taproot will get too woody.
But there is a great method to maximize the growth in year two when you start with fresh cuttings.
How to care for horseradish when using fresh cuttings
Use soft well drained soil and avoid dry outs. Horseradish is a root vegetable and prefers a well draining and loosely structured loam soil free of stones and other hard objects.
Hard objects like stones will make the roots split as it grows but is of course less of a problem when growing in pots and containers.
When you start indoors, cover the container or pot with plastic film to keep the environment moist and fertile.
Outside we can use grass clippings or wood chips to keep the growing environment moisty.
However, when we start plants with fresh cuttings we will grow the taproot for consumption while harvesting the lateral root growth for next year’s plants as needed.
A great tip for growing a larger taproot is to gently lift the plant from the soil when the plant is established and growing.
We then take a sharp knife and cut off the lateral root growing from the taproot only leaving the roots on the bottom thyroid og the taproot.
These remaining lateral roots will continue to feed and nourish the taproot where removing the others will allow the taproot to grow strong.
Another added benefit is that trimming the taproot will contain the spread of the plant.
And of course, any viable root cutting can be used for starting new plants.
Companion planting is the idea that planting certain plant types close to each other will create a growing environment that promotes growth or deter pests from entering their space.
In my experience the horseradish is quite sturdy and will successfully fight off posters as needed. And as it is invasive I do not grow it close to other plants.
Should I change I would choose potatoes, asparagus and rhubarb to be the companions to my horseradish plants. And from what I understand it is the companions that yield the benefits from the horseradish.
Propagation of horseradish – how to divide horseradish plants
Unlike when we extract seeds from for example tomatoes it is much more straightforward to work with the horseradish root.
If we use last year’s plant we simply remove healthy looking new roots growing from the main taproot. I keep the harvested roots in the fridge or a cool root cellar and bring them out when it is time to plant again in the spring.
Another alternative is to take fresh root cuttings from horseradish plants when harvesting.
Either way you will find that the horseradish is a sturdy perennial that will behave as long as you keep it well nourished and do not let it dry out.
Harvesting your horseradish root
The actual horseradish harvest is quite straightforward.
And actually, if you want, as soon as the plant is established you can dig up roots and harvest throughout the season.
If you grow horseradish in a small container like I do you can also dig up the plant when it is established and trim the roots. This will promote the growth of stronger and larger roots.
Regardless, my main tip when it comes to harvesting is to use a garden fork – also called a spading or digging fork.
The other alternative it to – if possible – simply empty the content of your container and use your hands to harvest the roots.
Trust me, most people are genuinely surprised when they realise just how big the roots grow if left unchecked.
Now, if you planted in a container with no bottom plate or have trimmed the taproot throughout the growing season you will of course have a more controlled area to harvest.
When we have lifted the plant out of the ground or container we simply shake off excessive soil.
One plant will yield enough to harvest for one family. The main taproot in the photo above measures almost 40 cm (16 inches). And there are also a large number of smaller but usable roots that will have us covered until next year.
Finely grated horseradish as a
My three favourite uses of horseradish are finely grated as a taste enhancer when cooking, oven roasted with other vegetables or sliced and used when pickling cucumbers.
Regardless, the flavour goes a long way. Try mixing it with your mashed potatoes next time.
How to store horseradish
When we harvest horseradish plants we are always surprised at how much horseradish one single container will yield.
As the horseradish flavor is very strong and a little goes a long way, we freeze horseradish for use throughout the year.
If you freeze horseradish you have to remember to grate it frozen. Do not defrost. Also, grated horseradish does not freeze well.
If you prefer you can of course also store fresh horseradish wrapped in plastic in the fridge for a couple of months.
But we always freeze everything that we will not use immediately as we find it more convenient.
To freeze you simply divide into portion size pieces and then wrap each piece individually in plastic food wrap. Then place all the wrapped pieces in a larger freezer bag for easy storage and place it in your freezer.
Now all you have to do is to take out as many portion size pieces as you need when you need it.
Frequently asked questions
Helpful resources: University of Vermont Extension