By Sue Robishaw – Cold-climate gardeners can boast few crops that prefer their freezing winter abode but the sturdy horseradish not only prefers it that way, it requires that cold. It does need a long enough growing season to grow healthy leaves and good roots, but if you plan on growing horseradish, know that the horseradish plant doesn’t need to be coddled through those unexpected frosts. It may not be a main eating crop, but it can enhance many less wild fare.
A hardy perennial of the mustard family, grated horseradish root has been enjoyed as a condiment for centuries. Not as common as mustard sauce in this country, it is still a favorite for many and well deserved of its special status. There are few crops that give so much for so little work.
I started growing horseradish in our first few years of gardening. Having read that it was good to plant when growing potatoes to keep potato bugs at bay, I carefully put roots at each end of the potato plot. As I was also diligently rotating all my crops in those days, following the expert advice I’d read, the venerable horseradish followed our potatoes through the garden. As I gained more confidence in my gardening skills and growing horseradish, I began to depend more on my own thinking and observation than the book lore. And it was soon obvious that the horseradish/potato team was one of those “better in theory than practice” recommendations. Not that they didn’t do well together, but the horseradish left a trail of persistent offspring behind while the potato bugs were content to follow the potatoes wherever they went, with or without the horseradish.
In spite of frequent and careful digging, I wasn’t able to clear the plots of horseradish until we moved our garden right out of that area. Even then the horseradish persists, and 20 years later it is still there among the grasses and plants of the field.
Though horseradish will grow in such conditions, it grows better roots for harvesting if given its own space and attention. It favors rich, deep loam and will not thrive on overly sandy or dry, gravely soil. And being a deep root crop, it needs depth to grow, so a hard subsoil won’t be to its liking either. But in the wide area between the extremes, which is pretty much any healthy garden soil, it will give you a good crop with little fuss. Plan on growing horseradish where its spreading habit can be contained. It’s a large-leafed, tall perennial plant so make sure it won’t be overpowering a more delicate neighbor.
Three years ago, in one of my many garden rearrangements, I invited our horseradish out of the field and back into the garden. I had space at the end of the new rhubarb bed which seemed the perfect spot. Being at the edge of the garden, it has tilled or hoed border on two sides, rhubarb on another, and a well-mulched path on the inside. A great home for growing horseradish. Though the bed was new, it was part of the old garden so the soil was good. Both the rhubarb plant and horseradish responded to these fresh, rich digs with such enthusiasm that I will be happy when the soil wears out a bit.
Though horseradish flowers, it seldom sets viable seed so propagation is by root or crown divisions planted in early spring or in the fall. It doesn’t take much of a root piece to get it growing. Horseradish is so hard to eradicate once established, but you’ll get a better plant (and root) with a good sized start of root or crown. Plant the crowns as they were growing originally, with the top level with the top of the soil, and the roots horizontally several inches deep in the soil, 12 to 18 inches apart in the bed. Mulch it well and let it grow, adding more mulch later as needed. As with most crops, if you have decent soil and a good mulch, you won’t need to artificially water the plants. They can handle the wet years and the dry years, the cold and the hot.
If well grown, the horseradish coexists amiably with the various insects that enjoy the plant. Flea beetles like to pepper my plants in the spring, but the leaves soon outgrow the onslaught and everyone is content. I’ve never had a problem with root maggots, but if you do, a sprinkling of wood ashes around the plants during the early season should help, as it does for the related radishes and cabbages. If your horseradish is overrun with pests, it’s likely your soil is not adequate for good growth. Work on the soil and let the horseradish and birds work on the pests.
The plants grow and the roots enlarge and thicken as the season progresses, working toward those tanned skinned, white fleshed, fairly firm roots that have such a fiery reputation to, as the 1937 Taylor’s Encyclopedia of Gardening says, “tickle the jaded appetites of the overfed.” Or simply to add some welcome spice to the homestead meal.
Horseradish roots can be dug any time the ground isn’t frozen. But as with most root crops, it is at its best in the fall, and even better after cold weather has arrived but before the ground freezes. This is generally when the bulk of the roots are harvested. You can harvest the first fall after you begin growing horseradish, but it might be better to let it grow another year to let it get established. The plant grows a large, long taproot with many branches and long side shoots. If you are going to grate the root by hand, you’ll want only the sturdy main root. But if you are going to chop or use a blender, then you can also make use of the larger of the side shoots.
When ready to harvest in late fall, I rake off the mulch, roughly dig up the main plants with a garden fork, and take the often branched main root and a number of the long slender shoots. There are many shoots and roots left throughout, and I rake the dirt back and let it go at that. Of course, there goes the nice and neat spacing, as next spring the plants will now grow here and there as they will. But it works and is an easy way to manage the plot. However, you can be more diligent in harvesting roots, pulling all you can find, then replanting six or eight-inch lengths of a pencil or small finger-size roots, or divisions of the crown of the main root as you did originally. There will still be many missed roots putting up small shoots, but the main plants will be as you planned and planted. This will probably give you a better crop.
You can also just dig up roots as you need them. If you have a thick mulch or deep early snow, the harvesting period can be extended until the depth of winter. Roots can also be dug in late winter/early spring when the ground thaws. But you’ll find when growing horseradish that the plant starts growing early so this harvest window is fairly small. Once growth has started, it’s best not to disturb the growing horseradish so it can put all its energy into producing good roots for fall, and not have to spend time repairing the damage done by mid-season harvesting.
If you want a continuous supply of horseradish sauce, you’ll need to store roots for making fresh sauce throughout the winter and spring. If well stored, roots can probably be saved and used on through the summer, but so far I haven’t had enough roots left to try that. Besides, for us, horseradish sauce isn’t as much desired in the summer.
Roots can be stored in slightly damp sand or leaves in a cool cellar or space. Use the smaller and damaged roots first, as the better roots will last longer. You could also dig a trench in the garden to store the roots with other root crops such as potatoes and carrots. Buried and covered with a thick mulch, they can be harvested until the snow gets too deep or the ground freezes. In early spring, these roots will be much fresher and in better shape than cellar stored ones. You run a risk of unexpected deep freeze or rodent damage, but the quality is worth the chance if you have enough roots.
The longer the roots are stored, the less pungent (relatively speaking) they will be, which can be a positive or negative effect depending on your taste. The prepared sauce also becomes mellower with age.
Our sauce experience is rather mild compared with true horseradish aficionados, though we’re quickly becoming heavy users. I barely remember the first sauce I made from a few roots grown in our first backyard city garden almost 30 years ago. But I do distinctly remember the result when I took the lid off the blender for the first time — gasp, gasp! Great stuff for clearing the sinuses. Instantly, and cheaply. Highly recommended.
After we moved to our northwoods homestead and having grown the stuff for several years, I decided I really needed to do something with it. At that time, I felt I had to can or preserve in some fashion everything I grew or could harvest. But the only thing I knew to do with the sauce was as a condiment with meat. And, living without refrigeration for the first time, we were well on our way to a non-meat diet. I did harvest some roots though and decided to make a sauce.
Our electricity was limited then and came from our sole solar panel. Besides, we had left the blender and other such encumbrances behind. So I got out the simple but effective common box grater and (the earlier horseradish eye-watering experience still fresh in my mind) took it out in the yard on a breezy day and grated up a half pint for sauce. It did wash out a few tear ducts but not nearly as violently as the blender in the kitchen had. I think I mixed it with vinegar, per the preserving books I had, but still didn’t quite know what to do with it. We not only weren’t eating meat, we didn’t have refrigeration. Living in our small cabin, we didn’t even have much of a cool spot. And the books said you had to keep the prepared sauce refrigerated. So we gave the sauce to my Mom and Dad.
But my growing horseradish was thriving, and I wanted to use it, so I figured I’d have to can it. Not knowing quite how to do that, I wrote to the one source I thought might be able to help, Countryside magazine. How, I inquired, does one can horseradish sauce? Hoping they (not knowing who “they” were at that time) might print a reply in a future issue. To my great surprise, I received a hand-written note back from the editor (also publisher, manager, writer, man-of-many talents), JD Belanger. One doesn’t can horseradish sauce, he (I assume with some restraint) kindly explained, it would ruin the flavor. He said he regularly made quarts of sauce, simply keeping it in the refrigerator, and eating it with breakfast eggs every morning. Quarts?! Wow.
Even when I moved my horseradish from field to garden, I didn’t seriously consider making sauce. It was as much for having good roots to give away that it made its way back into my life. A good friend, gardener and amateur chef, Peter Copenhaver, mentioned wanting to get some horseradish growing on his and Melissa’s new place. So the first harvest from the prolific new plot was a bucket of roots and crowns for him to plant and for sauce. Later he kindly gave us several half-pints of prepared sauce in return. So of course, we had to at least try it. But with what? No meat to eat it with, and since our years of raising chickens was long past, we seldom ate eggs.
A common supper for us in fall and winter is potatoes (baked if the heating stove is going) with various vegetables–whatever is in season or in storage-sautéd and steamed with onions and garlic. That’s what was on the table, so that’s what we tried Peter’s horseradish sauce with. Wow! It was delicious, and a great side for the potato dish. We were hooked. That sauce went fast.
It was too late in the winter to dig roots, but the following fall I harvested a good crop for both Peter and myself. We were back to making and eating horseradish sauce. But this time, there was no problem with how to store it. We ate it too fast for one thing, but I also found the sauce keeps just fine for many months in our cool root cellar.
Although I knew I could grate the roots with the grater, it’s a slow process. So the next trip to the St. Vincent de Paul store gained us a small, used blender. Our solar array was much larger now than our early one-panel system, and we could afford the electricity. Although still not fond of kitchen gizmos that take up too much space and time, I do like the blender for making horseradish sauce. However, we did the job outside in the woodshed this time which was much more pleasant. Mid-winter we took the blender out to the shop building to make sauce.
Peter’s sauce had a great flavor, so I asked him for his recipe. He didn’t have exact quantities, but this is what he thought he put in:
2 cups grated horseradish root
2 large cloves elephant garlic
2 tablespoons cane sugar
2 teaspoons coarse Kosher salt
1/8 cup extra-virgin olive oil
2 teaspoons ground prepared mustard
1/4 cup white distilled vinegar (maybe more)
Being a homesteader, I adapted Peter’s recipe to my own preferences. The second batch I remembered to keep track of the quantities. This is what I came up with:
Wash and scrape horseradish roots with a knife or carrot peeler. Grate or cut into pieces for blender
2 cups chopped horseradish root
4 cloves regular garlic
1/4 cup olive oil
1/4 cup maple syrup
1 teaspoon salt
1 cup cider vinegar (approximately)
If using a blender, add small quantities of root at a time with as much vinegar as needed to keep it working. Add other ingredients and blend to your liking, adding vinegar for a good consistency. Put in clean jars. Makes 3 to 3-1/2 half pints.
Be prepared, the fresh sauce is pretty potent. Some like it hot; while I like it better after it’s mellowed for a month. Either way, it’s a great accompaniment for a variety of meals, whether plain or fancy. You’ll find it on a healing herbs list as it is great for congestion, coughs, bronchitis and sinus problems. A great addition to the cold climate garden.
I hope this inspires you to start growing horseradish this season!
Originally published in Countryside in September / October 2005 and regularly vetted for accuracy.