[gardeners] Re: Horseradish and potatoes?

Tom Clothier (gardeners@globalgarden.com)
Fri, 20 Feb 1998 09:38:09 -0600

From: Catharine Vinson <cvinson@cris.com>

>I have some 4-square raised beds that are ready to plant and the height of
>the horseradish at the back of the beds would make (maybe) and interesting
>"hedge" of sorts. Also would be easier to keep them from invading other
>areas if planted in these particular beds. What say you guys?

They each respond well to intensive plantings, and you would most likely
be digging roots when there were no tubers left in the ground.  The tubers
like slightly acid soil, while the roots don't really care.  The specific
fertilizer for each plant need not interfere with the other, as each will also
produce with balanced fertilizers.  In your zone, you may have the luxury
of a 12 month horseradish crop, and you will be able to time harvesting
and planting to avoid competition. So it is feasible, and the potential
for becoming a garden disaster is very slim.

But I wouldn't do it.  I grow considerable quantity of both.  The potatoes
require 3 or more years soil rotation while avoiding soils used for other
solanaceae.  The horseradish is best isolated in dedicated permanent
beds.   In my area, the potato leaf-hopper is the only agent of blight, in
fact it is my only potato pest.  I have not seen them to be repelled by
specific plants, but only attracted to plants they like, especially potatoes
and green beans and hyacinth bean.  If they are repelled by volatile oils
within the leaves of certain plants, they could easily co-exist on potato
leaves right up close to those plants.  If they are repelled by odors given
off by the leaves of certain plants, will the repelling distance be more
than a foot or so?  If there was a class of plants that did repel this
menace, I would select an annual to interplant right amongst the
potatoes, one which  would be discarded at the same time as the
tubers were dug out, so that you would always be able to take your
companion plants to the next bed in your potato crop rotation.  Finally,
I think mixed beds work fine with herbs and ornamentals, but they
create a lot of unnecessary work in vegetable gardens (except for
lettuce and some greens).

zone 5a, NE Illinois, -21F Min