Cultural Practice
About 5 percent of all horseradish is produced without pesticide input. Market for the crop is principally the US. The market is primarily for precessed condiment.None of the Illinois crop is marketed outside the US.
Horseradish is a long season annual crop grown for its thickened root. Vegetatively propagated root pieces are planted in from late March to mid May. Root pieces root pieces 8 to 15 inches long and
one-quarter of an inch in diameter are used. Fields are thoroughly prepared by tillage after which crop rows are marked with a mechanical device, and the pieces then planted by hand. The soil is then ridged mechanically to cover the root pieces. Harvest occurs in early November. The field is first mowed to remove the plant tops. The vegetation is raked to the side or removed and the field is harvested with mechanical digging devices.
 
The field is harvested with mechanical digging devices, usually modified potato diggers, and the
roots are loaded onto hauling wagons. Wagons are dumped onto sorting lines in which excess soil is
tumbled off and larger root pieces are graded out. Sets are snapped off by hand from the parent root
and are set aside and stored in coolers or in outdoor pits over the winter for use in replanting the
fields the next spring. No treatment is applied to stored root pieces. This crop is primarily
rotated with field corn and soybeans, sometimes with vegetable crops.
 
 Insect Pests
 
The principal insect causing problems in horseradish is the beet leafhopper. Because it vectors the
"Brittle Root" disease the threshold for tolerance to this pest by the grower is very low. If more
than a dozen insects are discovered during the weekly area field scouting program, nearly every
field will be treated for the pest. In problem years, nearly 70-85 percent of acreage is treated
with an insecticide for control of this pest. No cultural controls for this insect exist.
 
Some cabbage, striped and horseradish flea beetle infestations do occur but are infrequent and
seldom are found at a level requiring treatment. However, emerging shoots after planting can be
heavily damaged at times by flea beetles. No cultural controls for this insect exist.
 
Diseases
 
There are limited leaf blights, spots (cercospora, white rust) that affect various horseradish
strains. These are typically at non-economic levels, though weather conditions may warrant
treatment. Soil born verticillium is an important root disease and is currently being addressed by
varietal resistance and by the use of soil fumigation. The following fungicides are registered for  use on horseradish:
 
 * Ridomil 2E
 * 50W
 * Gold EC
 * Gold WSP
 * Telone C-17 and Telone 2 are currently used on about 10% of the crop as a soil fumigant,
 primarily for the control of soil born fungi and nematodes in problem areas.