Food fads have changed our dining choices over the past 50 years from bland meat and potatoes to spicy, piquant foods our grandparents never dreamed of. Some changes have come about by immigration of refugees from wars and their desire for “home” food, and other changes from less obvious sources. For one thing, our taste preferences have grown hotter. Nearly 25 years ago, salsa (tomato, onion and chile) began outselling ketchup as a condiment in this country, and since then, tastes for even hotter chiles and sauces have come available.
More recently, snackers have taken to poppers (cream cheese-stuffed jalapenos), and dip recipes now are even hotter. Many endure the burn of habaneros for their fruity flavor that accompanies heat. We can grow most hot chiles in our gardens, but there are different kinds of heat, too.
Wasabi, that plant some call “Japanese horseradish,” finally came to America just a few years ago. This Japanese member of the Brassica family holds heat only briefly, a heat akin to that of horseradish or an intensely-flavored mustard, unless powdered or grated with a heat-holding substance. Wasabi is difficult to grow, thriving in Japan at the edges of streams like watercress, but said to be touchier about growing conditions. Its heat is quite different overall than the capsaicin in hot chiles.
Horseradish is much easier to grow than wasabi, but there are some cautions for the home gardener. It easily becomes invasive, spreading mainly by bits of root left in the ground, and by seed from plants that are at least two years old. Not all of its seeds are viable, but unless you want this crop to spread, remove blossoms when they appear. It’s sufficiently difficult to contain horseradish’s rising from bits of root. You don’t need to watch for seedlings too.
It’s a member of the mustard family, native to eastern Europe and western Asia, that is so pungently powerful in assailing nasal passages that it was regarded as a medicinal plant at first. Its heat is allylisothiocyanate or mustard oil, rather than capsaicin of peppers. Horseradish grew wild in parts of England in the 1500s, known there as Raphanus rusticanus or Red Cole. It was so powerful and dangerous it was not regarded as a proper medicine for women, just for laboring men with less delicate stomachs. The herbalist John Gerard noted that the Germans mixed some of the root with vinegar and used it as a condiment on meat and fish, but he didn’t advocate its culinary use to Englishmen.
Due to problems of unwanted spreading of this plant after harvest, some folks plant in a bottomless five-gallon bucket. It would probably be easier to water the plant if you bury the bucket, but remember, any tiny piece of root you leave in the soil after harvest will result in regrowth of the plant.
Home-grown horseradish is best and easiest to use if it has a single straight taproot, so prepare your soil by digging deeply, at least 12 inches, or deep enough to bury a bottomless bucket, and then filling with loose soil rich in organic matter. Some folks advise using a lot of manure in that hole, but manure’s blamed by some for carrots’ forking. Since most uses of horseradish require grating, keeping its root growth to a single root is important.
Brush off all side roots from the root section you’re planting before putting it into the soil. An old wartime Victory Garden reference advocates pulling the plant when it’s about four inches high, brushing off side roots, and then replanting it.
Harvest is usually late fall —October or November — by pulling or digging the root, washing it, then grating it. A Master Gardener classmate advised, based on his own experience, grating your horseradish outdoors so the pungent fumes won’t overwhelm. Adding vinegar to the grated root tames the pungency of the horseradish to some extent, and it preserves the heat.
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