They're pretty cheap. Though it seems you won't have a usable root for a year: https://www.etsy.com/listing/224025676/horseradish-sets-starter-plants-root?gpla=1&gao=1&&utm_source=google&utm_medium=cpc&utm_campaign=shopping_us_c-craft_supplies_and_tools-floral_and_garden_supplies-greenery_and_gardening-other_greenery-other&utm_custom1=085b6236-5906-4018-8448-6cb6947ba357&gclid=EAIaIQobChMIudHL35T32AIVyxuBCh32tw_aEAQYBCABEgK8lPD_BwE Evidently the greens are edible: https://www.thekitchn.com/how-can-i-use-horseradish-greens-220790 http://www.cooksinfo.com/horseradish-greens http://homeguides.sfgate.com/horseradish-leaves-poisonous-80115.html