Plant Lists - Much of the information relating to the
relative toxicity of the substance,
juglone, produced
by the roots of walnut trees is based on personal
observations of horticulturists and
gardeners. There have
been only a small number of controlled experiments to test
various plants. Therefore, the lists below are a "best
guess" of landscape plants that are or are not impacted by
growing in the close proximity to walnut (or other members
of the genus,
Juglans) trees.
As you will note, these lists
are rather limited in scope compared to the vast
number of landscape plants we grow. It is our conjecture
that plants that have not found their way onto these
lists
are most likely not affected. Certainly, if the plant is one
that is very commonly grown in landscapes and was impacted,
it probably would have been reported. Also, rare plants that
have recently found their way into landscapes may not have
had enough experience to be listed.
Finally, you will note that
some genera appear on BOTH lists. That is because someone
has noted specific cultivars that are susceptible and other
cultivars of that are not. Oh, well...
