Pinellia cordata
Roy Herold (Tue, 31 Oct 2006 05:04:24 PST)

Well, I never expected to have my name mentioned so many times in the
course of a PBS thread. Go figure.

I believe most of the facts (or assumptions) regarding P. cordata have
already been presented. The first thing that everyone who grows the 'Roy
Herold' form should do is change the label to P. cordata 'Yamazaki'. As
John Grimshaw mentioned, both he and I acquired it from the ARGS seedex
in 1992. I had never grown P. cordata before, and had no idea that the
'seeds' were really bulbils (or tubercles as John calls them). As the
plants matured, I was impressed by the fact that the leaves had
wonderful silver markings, and were the most attractive of aroids that I
had encountered. Then there were the great tropical fruit (or bubble gum
or whatever) scented flowers...

I first remember seeing other forms of P. cordata on a trip to Japan in
1995, where it was common as a small pot plant in nurseries and on
doorsteps. I really didn't think all that much of them, as the smallish
(maybe 4" x 1") leaves were not that well marked, and puny compared to
the ones on my plant which commonly reached 8" x 3". I believe I saw the
same small form at Don Jacobs' nursery.

I never ventured to grow it outside here (N of Boston, Zone 5b/6a) until
I encountered the small form growing happily outside in a number of
gardens and nurseries in Ann Arbor, MI. I put a few of mine out, where
the main tuber promptly died, but the little tubercles found there way
to better locations and they kept going. Most of mine are still in pots,
however.

John G. and I later discovered that both of us had a superior form, and
confirmed they were the same clone by exchanging tubers. In seeking a
name for this form, I went back to the seedex list and found that they
had been donated by a Mr. Yamazaki in Japan. I wrote him to ask
permission to use his name for the cultivar but received no reply,
probably due to the language. John went ahead and used the name in his
article, and I guess we're still trying to make it stick.

Regarding cultivation, I have found that they do like cool summers and a
well drained situation. This summer, which was particularly hot and
humid here, they went dormant quite early, probably early August. During
cooler times, they go right up to frost. Also, I have never seen them
set seed but once, and that was on a single inflorescence. I sowed the
seed, they germinated, and the offspring were identical to the parent.

As for sources, I believe Ellen Hornig has sold Yamazaki from time to
time (didn't check her latest list). I should be able to find a bunch of
Yamazaki tubercles that I can send in for the BX, but probably not til
December after I return from South Africa. Anybody in ZA who wants some?

--Roy