Arisaema sikokianum

[Andy Y.S. Wong]

In 25+ years of viewing and growing very many Arisaema sikokianum, I
have not seen an offset, although other gardeners have told me that they
have.  Most if not all arisaemas can, under certain circumstances,
sprout from dormant buds on the corm if the terminal is damaged, so
maybe that is what happened in those rare cases.  Certainly, sikokianum
plants can live for many, many years under ideal conditions, but as Anne
mentioned, they can exhaust themselves through heavy seed production to
near-death.

In the wild, A. sikokianum often grows in loose partly decayed litter on
top of the underlying soil.  It is almost impossible to give them too
much drainage.  Insufficient drainage probably kills more sikokianums
than anything else.  Coarse sand with a little humus seems to be a very
satisfactory medium for good growth and long life.  If an otherwise
well-drained site is inundated even for a few days there can be
problems.

As I mentioned in another posting, we have the best results in the
garden on steep slopes in very well-drained soil.  We have learned to
plant them in areas that dry out in mid to late summer.

Another reason for disappearing corms is the critter problem. While many
arisaema species are not tasty to critters, sikokianum is unfortunately
an exception.  The biggest threat to field production of sikokianum in
Japan is wild pigs; a few of them can clear a field overnight.  They are
not fond of most other species.  So if you have voles or chipmunks (or
wild pigs) and disappearing sikokianums, you can connect the dots.

In Japan I have seen one year sikokianum seedlings with flowers in
nursery beds.  I have never seen that happen with other species.

Barry Yinger and Andy Wong