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  A. titanum ???
From: "Julius Boos" ju-bo at email.msn.com> on 2000.03.31 at 21:54:57(4289)
Dear Paul,

I read with MUCH interest your posting where you reported to the GREAT
surprise of many growers of this normally difficult species your sucess
in growing and flowering it under seemingly VERY adverse conditions, I even
forwarded your posting to Donna Atwood at Selby who is keeping track of who
has bloomed this monster.

The opinions are that it is unlikely that 'true' A. titanum can or would
grow and bloom under the conditions you describe, and that you may in fact
NOT have A. titanum, but have A. paeoniifolius, a widly distrubited species
which is even grown commercially in Jamaica, and the tubers exported to
Florida where they are sold as a food item in Indian ethnic groceries.
This (A. paeon.) is a species that can get huge, leaf up to 10 ft tall, and
which can and will thrive under the conditions you describe, and could be
easily mistaken for true A. titanum.

Perhaps you could be so kind as to tell where you obtained the seed or small
original plants of A. titanum, as all the ones in cultivation came from few
sources, and also post a photo of the infloresence of your plant on the list
for a positive
I.D., as IF your plants are in fact A. titanum this additional info. would
be very valuable to the growers who struggle to keep this tropical 'monster'


Julius Boos

From: "Wilbert Hetterscheid" hetter at worldonline.nl> on 2000.04.01 at 15:11:16(4300)
To make sure you may have paeoniifolius, just fumble the leaf stalk up and
down and when it feels roughish, it is paeoniifolius, when it is smooth,
well it could be anything.


From: "Julius Boos" ju-bo at email.msn.com> on 2000.04.01 at 15:15:13(4305)
Dear Paul,

The following may be of help to you in determining what species you actually
The petioles of A. titanum are described by Wilbert Hetterscheid
as --petiole 1-ca. 5 m long (3-15+ft!!!)20-30 cm dia at the base, SMOOTH,
green or dark green with large oval to rounded, pale green spots. The
spadix of the inflorsence is basically a long, thinish conical structure,
tapering from thickist near it`s base to it`s tip, with no increase in size
or swelling in/near it`s middle. The spathe is a dark, bright purple with
pleats like a skirt that extend from it`s to it`s inner base outwards to
it`s edge.

In A. paeoniifolius the petiole is described as---petiole to ca. 2 m long
(+-6'), background color pale to dark green or blackish green, usually with
large and small blotches and numerous tiny dark dots, the large blotches
often confluent, especially near the base, SURFACE SHALLOWLY CORRUGATE TO
STRONGLY ECHINATE-VERRUCATE. In other words, the petiole is
generally/commonly NOT smooth in this species. The spadix also 'balloons'
out just above the male floral zone, then tapers quickly to it`s tip, lots
of deep vertical 'folds' occur in it`s circumference. The spathe varies in
color, being from pale green to dark brown, usually with large and small,
circular paler spots, inside basal area colored deep maroon, upper zone
dirty whitish or very pale pinkish.

The above should give you a guide to determining what species it is that was
given to you. Continue to try to speak with your friend on St. Croix to
detremine the source of her plants. There was a photo published in an
early 'Aroideana' that mis-identified a HUGE leaf of an A. paeoniifolius as
being that of a A. titanum, but this error was subsiquently corrected in a
later issue in the 'errata', and maybe this is the source of the possible
error in the I.D. of your plants??

Hope this helps,



From: "Paul Kruse" pkruse2000 at mindspring.com> on 2000.04.02 at 04:21:26(4310)
Thank you for your help in the matter. Your message backs up the data I
received from Julius Boos. I does appear that the plant is A.
paeoniifolius. I am still playing phone tag with my Botanist friend, and the
source of the plant. I will let you know what I find out, hopefully Sunday
morning. Thank very much for your interest.

From: "Julius Boos" ju-bo at email.msn.com> on 2000.04.02 at 04:21:48(4311)
Dear Paul,

It is good to be able to make what now appears to be a positive I.D. of the
plant you honestly thought to be A. titanum as being in fact A.
paeoniifolius!! The rough petiole is the clincher.
This is reassuring to the growers who struggle to keep 'true' A. titanum
growing and alive!

Continue to enjoy growing your plants, ALL species are wonders of Nature!!

Thanks for your help in this attempt.



From: SelbyHort at aol.com on 2000.04.02 at 14:59:12(4314)
We once received a huge tuber here at Selby that had been incorrectly labeled
Amorphophallus titanum. This was back in the early 1980's, and the tuber came
of of South Florida. I suspect someone there was distributing lots of A.
paeoniifolius with the name A. titanum around that time. Anyway, this
impressive tuber was planted on the grounds with much fanfair, and there was
even an article printed in Aroideana showing the massive plant in leaf, with
the caption that it was A. titanum (this may be the picture of the leaf that
you are thinking about, Julius). However, once the thing bloomed it was
obviously the wrong species, and if anyone had know, we would have realized
even before flowering that we did not have A. titanum because the petioles
are so different. I have pictures of Mike Madison carefully planting the
tuber, and some later pictures of the inflorescence. It was disppointing to
know that we only had A. paeoniifolius all that time, but one should not
dismiss this species so quickly. Amorph. paeoniifolius makes an impressive
specimen in the S. Florida climate and thrives here, so is a wonderful
addition to our sub-tropical gardens. This species, along with several others
such as A. konjac, A. bulbifer, A. muelleri (once referred to in FL as the
"sweet smelling bulbifer" and still often sold under the name A. bulbifer),
Gonatopus bovinii, etc. will grow quite nicely in the garden, some of them
multiplying to almost become weeds. It would be fun for someone to try more
Amorphophallus species outdoors in Florida gardens to test cold hardiness,
thus expanding our palette of Amorphophallus for outdoor horticulture.

Amorphophallus titanum is just not hardy enought to live outdoors here,
although we still have one plant in our Oak Grove that was planted about 5
years ago. It has dwindled each year and will probably never get large enough
to flower, because it seems to be forced into dormancy each winter, usually
by early December, from cold temperatures. This plant generally has not
resumed growth until late July each year, so there has not been enough
growing time each season each to bulk up the tuber. This plant is now half
the size of the greenhouse grown specimens that were all grown from the same
seed batch.

From: "Paul Kruse" pkruse2000 at mindspring.com> on 2000.04.02 at 18:23:04(4319)
I just sent an e-mail to Julius Boos concerning my Amorphophallus sp. It
appears that it is indeed A. paeoniifolius. An e-mail to someone else, from
Selby Gardens, stated that in the early 80's someone in Florida was selling
these corms by mail and identifying them as A. titanus. I will still keep
experimenting with making it an attractive indoor house plant. thank you
for your assistance in this matter.

From: "Paul Kruse" pkruse2000 at mindspring.com> on 2000.04.02 at 18:23:24(4320)
Donna Atwood. It appears that I almost certainly have Amorphophallus
paeoniifolius (at least not A. titanum). My botanist friend, source of my
present plant, doesn't remember the source of her tubers. Your information
concerning a S. Florida source mislabeling their corms is most interesting.
I received my first two plants by mail in 1980. The instructions stated
that after the plants bloomed, the corms rotted. According the
instructions, the dark bumps on the bottom of the corm should be cut out,
air dried, then planted to produce new plants. I did this with one of my
plants and did get a couple of new ones. The other corm evidently did not
read the instructions and resprouted anyway.

I suppose it's just as well that I don't have A. titanus, since I live in a
small apartment. My present plant makes a beautiful house plant and I am
going to continue experimenting on fertilizer and minimum light
requirements. Your letter was very helpful. Thank you. Paul Kruse

From: "Julius Boos" ju-bo at email.msn.com> on 2000.04.02 at 18:23:51(4321)
Hello again Paul,

>Good morning Julius. I just received a telephone call from my friend on
Croix. She is in her upper 80's and very vigorous, however, she no longer
remembers where her two corms came from. The other plant still comes up
every year and blooms on occasion. I have remembered that the three corms I
obtained in 1980 were ordered. They were labled A. titanum.<

You will note the posting of my friend Donna Atwood from Selby Bot. Garden
where she says that they also received a tuber of what was labled as being
Amorphophallus titanum, and that this event ALSO occured like yours in the
'80`s, same time frame. I`d BET they were from the same misinformed
source, and yes, the photo I remember was of the one that grew at Selby and
was published as A. titanum. We now know for sure all were A.
paoeniifolius, a much commoner and easier to cultivate species.

> I now suspect
that they could have been paeoniifolius. The instructions that came with
them said that the corms rotted after blooming. They said the only way to
grow new plants, after blooming, was to cut out the dark raised areas on the
underside of the corm and plant them. I did this with one of the corms and
did get a couple of new plants. The other plant, after blooming, came up

This too is a misconception that needs to be corrected, as several of the A.
titanums now in cultivation mainly from seed collected by the late Dr. Jim
Symon have continued to grow after blooming with no ill-effects.

> I guess its just as well I don't have A titanum. It would be
rather tight in my small apartment. Thanks ever so much for your help. The
local botanical society hs just received a gift of a large plot of land and
plans to put in a very large botanical garden. Considering the upscale
nature of Naples, it should be a good one. Thanks again, Paul<

Thanks again for going to all the trouble to obtain the information which
allowed us to come to the correct conclusion concerning the correct I.D. of
your plants as being Amorphophallus paeoniifolius, which as you recognise is
a good thing! A. titanum, with it`s up to 15 ft. tall leaf with a spread
of up to 21 ft., and 150 lb. tuber would indeed be a tight fit in you
This conclusion prevents misinformation from spreading on this list
concerning this wonderful group of plants.
Write when time permits,
Good growing!!!


Julius Boos

From: herm hermine at endangeredspecies.com> on 2000.04.02 at 19:18:51(4323)
At 11:23 AM 04/02/2000 , Paul Kruse wrote:
>Donna Atwood. It appears that I almost certainly have Amorphophallus
>paeoniifolius (at least not A. titanum). My botanist friend, source of my
>present plant, doesn't remember the source of her tubers. Your information
>concerning a S. Florida source mislabeling their corms is most interesting.
>I received my first two plants by mail in 1980.

I REMEMBER THE FAKE A. TITANUMS. at the time they created a wee stir. i
remember they were too inexpensive to be the real deal. HOWEVER, i thought
it was an honest mistake.


From: SelbyHort at aol.com on 2000.04.08 at 01:06:17(4352)
I would have to dig back in the records to find out more about this name
mix-up, but it was certainly not a deceptive act...I am sure that the source
of the corms sincerely believed that they were Amorphophallus titanum. We
have to be thankful for all the recent Amorphophallus papers and discussion
that have taught us more about this genus. This kind of information was
simply not available in the early 1980's.

Donna Atwood
Selby Gardens

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