|I just harvested my horseradish. Several older roots (2 yr) were beginning to produce a hollow area within the root. A couple of other roots were punky.
The horseradish was planted 6 years ago in a 5 x7 x2 confined box of peat/sand mix. I harvest about a third of the box annually and it produces 12-14 pints of the best ground horseradish in the world!
My question is: Does such a toxic plant have enemies (root rot, etc)? And, if so, how do I combat them. Will the root produce indefinitely in a confined space if harvested on a regular basis? Or, does it's own inbreeding weaken the stock?
I water and fertilize regularily as I have in the past, but feel that the root productivity has diminished.
|Although horseradish is a perennial plant, many gardeners treat it as an annual and plant it fresh each year. In theory, the bed will continue producing indefinitely. However, older plants usually yield progressively smaller and tougher roots each year. It sounds like you have been fortunate to have harvested quality roots for 6 years! (Since the plants are likely regenerating by the roots, rather than by seed, inbreeding wouldn't be a factor in the bed's decline.)
One way to prolong your bed is to harvest pencil-sized roots and save them as planting stock for next year. Store these roots in a cool, dark place that won't be subject to freezing. Replant next spring. That way, you can amend your soil each year, adding lots of compost andother organic matter to ensure a rich, crumbly bed.
Other causes for tough or hollow roots include overfertilization with nitrogen; horseradish is also prone to a number of root rot diseases.