About Arisaema sikokianum

[Susan Cox]

Hello All,

For everyone's information:

I have tried to grow A. sikokianum several times now and have not had
been successful, so having an interest in the questions posed on the
list I did a search.  Eventually, I ran across the Alpine Garden Society
of Tokyo, Japan and got a response from an 'expert' (sorry all you
experts out there, but since this person lives with them, he MUST know
something we all don't know......right?)  Anyway,  here is his
enlightening response for at least some of the key sikokianum questions
asked here on the list.  He gives a good idea of how they grow in nature
(location, soil, temps. and season of growth, reaction of plant after
seeding, tendency to get smaller after seeding, if they have a tendency
to die after seeding, does sikokianum produce bulbils, and anything else
you can glean out of his information).  There are other questions not
answered, such as why Donna's giant plant never gets smaller after
producing seed.  A few questions come up like, is it possible that
Donna's sikokianum is a hybrid of any kind, or is it because it stayed
female rather than reverting back to male as they can do in the wild as
well as in pot culture in Japan.  Donna, you might dig that sikokianum
up just to see if the mother plant produced bulbils also, or if maybe
fertile seed germinated next to it.  I didn't ask if they would continue
to grow larger only if they remain female, but I will.  Could this be
the case with Donna's plant?

The Alpine response:

>Many Arisaema species distribute in Japan, and A. sikokianum
is one of the most unusual and beautiful species.
I'm very glad to hear they are grown abroad.

I'm not so familiar with temprature in F, because in Japan we usually
use
celsius (centi digrees).  Anyway I give you the information about A.
sikokianum.
This species is growing in limited area in Honshu Is. and  mainly in
Sikoku
Is.  Sikoku Is. is in warmer temprate zone. The range of temprature
would be
0C-35C.  It means in Winter lowest is 0C, sometimes below 0 but never
freeze in soil.
And in Summer it might be up to 35C, but at night 25C. So your place is
good
for their growth. In Japan rainy season is in summer and in winter
climate is rather dry.
They live in open forest and grow in leaf litter.
They need much water and fertirizer when they are growing (from April to

September) and like moisture. Good drainage is essential. When we sow
seeds of
Arisaema, we usually wash off any flesh of fruit. Then keep moist untill
germination.

After A. sikokianum sets seed, the plant never die, but the tuber get
smaller than before and may become male plant again.

A. sikokianum never produce bulbils, propagation from seeds
is necessary for this species. A. thunbergii or related species
make many bulbils.<

I hope this helps,
Susan Cox