Hardiness of Pinellia cordata
Roy Herold (Tue, 02 Jun 2009 04:17:50 PDT)

One other point that I forgot to mention...

In the late 1990s I saw Pinellia cordata growing quite happily in
several gardens in the Ann Arbor, Michigan area, which is certainly a
subzero F region. These appeared to be established clumps as opposed to
spring replants. However, the leaf size was smaller and had less
variegation than the Yamazaki clone, so it may have been a hardier
strain. Most of the plants I have seen in gardens or nurseries in Japan
appeared to be the small leafed type.

And out of thousands of flowers, I have only had one set seed. The
special gnat that does the pollinating must have been around that year.

--Roy