Horseradish sparks opinions as strong as its taste. Most people, truth to tell, want nothing to do with the root in its fiery, ground-up form. Their relationship to horseradish rests mainly on acting horrified when Uncle Frank dashes some onto his roast beef sandwich.

Horseradish gets a bad rap. Unlike cabbage, a close relative, it does not befoul an entire city block with its odor when prepared. Nor does it refuse to give up its stranglehold on the human palate, like garlic or onion. Also, too many of us confuse the pure stuff with condiment atrocities that mix noble horseradish with mayonnaise, salad dressing, sour cream, and whatever mystery mash goes into cocktail sauce.

Early June marks the traditional date of an Illinois tradition: the International Horseradish Festival in Collinsville. According to local boosters, the area boasts a major center for horseradish agriculture, with perhaps sixty or even eighty percent of the world’s horseradish grown nearby. The Festival offers visitors a chance to learn about the plant, prepare their own horseradish, and of course eat the grated-up root in order to clear the sinuses, but how. Vendors even offer a fresh horseradish free of preservatives and made according to a secret recipe.

Potash is a big part of the Collinsville secret. A salt that doubles as a potassium delivery system, potash is abundant in area soils, part of a nutrient infusion provided by the nearby Mississippi River over the years. Potash locks heat into the roots. Grating up horseradish, meanwhile, releases an oil in the root that allows an eater to fully experience the trademark hot sensation.