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  Amorphophallus costatus flowering
From: Eric Schmidt <leu242 at yahoo.com> on 2008.12.08 at 20:52:59(18779)
I assume this is Amorphophallus costatus. It was
donated a few months ago and had this tag and a A.
macrorhizus tag in it. The leaf died down about a
month and a half ago and now the inflorescence is
coming up. Does this one get a bad odor?




From: "Wilbert Hetterscheid" <hetter at xs4all.nl> on 2008.12.10 at 06:37:39(18781)
Hi Eric,

I am afraid it is The Great Invader......... Am. konjac. You've been


From: <ju-bo at msn.com> on 2008.12.10 at 10:46:49(18782)
> Date: Mon, 8 Dec 2008 12:52:59 -0800
> From: leu242@yahoo.com


From: Eric Schmidt <leu242 at yahoo.com> on 2008.12.10 at 15:03:55(18783)
Thanks for the ID Wilbert.

Thats kind of disappointing but its alright, we never
have gotten A. konjac to grow here, the nematodes in
our sandy soil always get them. I will keep this one
potted up. Now we have a flowering specimen.

It has opened today and is emitting odor. Is that
abnormal for the leaf to have died down and then an
inflorescence come up a month and a half later, and it
is in Dec. ?






From: "Christopher Rogers" <crogers at ecoanalysts.com> on 2008.12.10 at 16:16:28(18784)
It looks like A. konjak to me . . .

D. Christopher Rogers



From: ronmchatton at aol.com on 2008.12.10 at 17:06:16(18785)
Am. konjac unfortunately. It probably was obtained from the same
person who sold several rare species on ebay and delivered konjac

Ron McHatton

From: ronmchatton at aol.com on 2008.12.11 at 07:16:00(18787)

It's not just nematodes that are a problem with this species in Central
Florida. Our soil is evidently way too hot and the tendency to be very
wet late in the growing season all contribute to problem. Some
individual clones do reasonably well and others, expecially large
plants are very susceptible to erwinia infection. I have the best luck
with them potted and in a very well-drained medium and I try to keep
them dry when we tropical storms or worse.

I have one that's in bud now. In colder climates, they have a very
well-developed cycle and flower in March or April. Here in CF, they
can evidently flower any time of the year and they typically, if left
potted, will flower a couple of months after the growth goes down.

Ron McHatton

From: "Wilbert Hetterscheid" <hetter at xs4all.nl> on 2008.12.11 at 07:20:49(18788)
Hi Eric,

You're wellcom. 1.5 month is quick but Amorphs which are mature enough to
flower, usually start the flowering earlier than when they would produce
another leaf. Whether it is December or not is not an issue for a
(sub)tropical plant. Whatever the season, when an Amorph loses its leaf and
is ready to flower, it will usually do that within a more-or-less internally
determined period after the leaf disappeared.


From: <ju-bo at msn.com> on 2008.12.11 at 11:28:39(18789)
Dear Eric,

Yes, the leaf usually dies down, and a few months later a bloom is produced.  Since A. konjac is usually grown in cooler climates (I recall seeing several which were grown in the ground in bloom   at Dr. Tom Croat`s home in Missouri!), the corm usually will go through a dormant period in the winter, and when the warmth of Spring sends the corm a ''signal'', the dormant corm then produces a bloom.   Because the corm was shipped to you in Florida probably from a cooler Northern region, the warmth of a Florida ''winter'' probably sent a false ''signal'' to the corm that Spring has arrived, hence the early bloom.
Further information about the odor emitted by blooming Amorphophallus, there are many funny tales about this, two are--
 A guy comes home to find his house surrounded by emergency trucks and personnel.  His Mum had called them, as his dormant corm which he had stored in his basement had bloomed, and she thought the bad smell was a gas leak!
Another was a guy seeing his roof covered in Turkey Vultures, they had followed and come to  the smell of a blooming A. konjac in his collection.

Good Luck,


> Date: Wed, 10 Dec 2008 07:03:55 -0800
> From: leu242@yahoo.com



From: Adam Black <epiphyte1 at earthlink.net> on 1970.01.01 at 00:00:00(18790)

Up the road at Kanapaha Bot. Gardens in Gainesville, FL we have one konjac near the entrance that has always flowered at this exact time (early December), while all others in a seperate mass planting of A. konjac flower around March-April. I can't think of any differing conditions between these two plantings that might affect flowering times. I have always found this one plant on a "reverse cycle" to be very interesting. Considering A. konjac's temperate natural range I wouldn't think a winter flowering period would be an effective adaptation - that is assuming this is a clone that is programmed to bloom at this time and not being stimulated by something yet to be determined. Come to think of it, I haven't been paying attention to our confused plant lately and will have to check and see if it has tried to send up an inflorescence , which most likely has already been knocked back by our recent freezes.

Adam Black

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