I've been TRYING to grow this one and decus-silvae from seed that I got for free.....they germinate easy of course like almost all Amorphs, but I find them to be more difficult than either titanum or hewitii....I've had many bite the dust while putting up a second petiole....they look very pale and not at all happy right next to my titanum and hewitii that are going like gangbusters. I'm going to give away any of mine that are still alive this spring to the botanical garden near my home if they want them....just to picky for me to bother with!!

They are evergreen just like the other species from Indonesia...keep them hot and humid all year if you are hoping for success.

Best of luck :o) Dam

I am rather relieved to hear of your lack of sucess with gigas & decus-silvae Dan, as I thought I was the only one suffering losses!
Not that I am doing much better with my titanum :(

Still looking for the knack at growing these amazing plants..

cheers

bill

I think you will do better with the titan, as they are hardy little devils. A real beginners aroid if you merely want to grow one and aren't to fussed about how fast it grows, flowering time or pollination.

Have you grown your titan from seed? Tubers riddled with root nematodes are harder and die at the slightest discomfort though, and I think this is how they got their un-deserved reputation of being a challenge.

Hi Rubbleshop, Yep, I've grown all of mine from seed....I simply refuse to pay $40-50 for a silly Amorph and 2 yrs. ago when I got my seed the seedlings were being sold for $100.....can you believe that....complete nonsense if you think back!! My understanding is that they get tougher when they get bigger.....it of course becomes harder to control water in a 20-50 gal bucket than in my little 8" pots that I've got mine crammed into now. I really have no place to keep it once it gets beyond maybe 6 feet tall so if I keep them alive that long I'll be donating them all to botanical gardens that might want them around here.....either that or put in a greenhouse....not likley....you're talking roughly $5,000 to heat it over the winter in my climate....maybe someday, but not likely. I agree though that so far titanum is by far the easiest of the Indonesian giants to grow. I've just got one going dormant now so hopefully it will wake up again very quickly....it is the dormancy that bothers me. When they are actively growing I keep them rather dry and they have done well to date.

Good luck on the gigas and decus-silvae......not worth the hassle in my opinion :o) Dan

Hi bluebonsai101,

Even the first leaf seedlings of titan are quite hardy. If you are not going to grow them on to flower, then there is no rush, so just keep them above -2C (28.4F) and they normally remain healthy. Where I live, that means they sit dormant for almost 1/3 of the year, so I am always impatient and heat mine to over 10C, but have a few which I have "held back" by leaving them out in an unheated greenhouse and the leaves still look very healthy, though there is no growth at the moment. I think that mis-treating them like that, they would take about 18-20 years to flower though, but they certianly don't drop dead.

I have never known them fussy enough to care about control of water - they aren't like Tacca!

Dormant titans usually grow again as soon as they reach 10 C (50F).

Hi Rubbleshop
I lost two Titan seedlings this winter. One had done really well for about 5 months them went dormant (or dead!!) As I later found the seed/tuber completely rotten. :(
The second seedling started, stopped, died! I have one more and also a young tuber. Both growing ok for now in my warm kitchen. I am being even more careful over watering, but had thought I had been careful with those other two as well!
How much water do you give yours when they really do go dormant?
I use a mix of peat,perlite and sand in my mix- is that too boggy? I now tend to wait till it is almost bone dry before watering. Until I get the watering right I will never suceed!
My others gigas and decus-silvae did really well until they started sending up a second leaf and them conked out!!

How do you know whether you have a lowland or highland form of Titan? Where did you get your seeds from?

cheers

bill

All my titans are the highland variety. I have a friend who's son owns a diving training school in Krabi, Thailand, who sometimes takes his boat to Sumatra, so I know where mine came from as the native people collect the seeds off the plants which get ploughed down during forest clearance and sell them.

It may be the variety you got as the lowland ones are more difficult, or even weak seeds from a weak parent flower, but my guess is that your compost wants a bit more sand adding.

Mine get watered when their compost feels dry to my fingers. If I can feel the coolness of moisture, they don't get watered. On the other hand, in summer it rains on them most days. I have had them growing happily in pots with moss growing on the top even.

With the exclusion of immediately after flowering, when they do have a short rest, mine never lose their leaves. A new leaf starts before the old one is shed. When I say dormant, what I mean no visible growth taking place.

If they were to lose their leaves I would give no water at all as they have enough water in their tubers to start re-growing, even if they were out of the soil in sawdust. Mine always have a leaf though.

I think there are a selection of sub-species, so maybe yours should go properly dormant - I don't know.

Interesting!! I think peat is a disaster for this species...or any species in my climate...I can rot konjac in peat in my zone 6a, wet summers. The botanical garden here has many Am. titanum and so I use what they use....2:2:1 turface (this is high fired clay), pine bark and charcoal. Mine are on heat mats continuously and in a south facing window....they get watered once every 5 days....the top of the soil is very dry then, but down near the tuber their is a tiny bit of moisture. I've only had 3 go dormant in 20 months....I mean dormant by the way....they are never, ever allowed to dry out. I think if you post to the aroid-l and ask the growers over there they would advise against allowing them to ever dry out completely, but there is likely a difference in growing conditions I suppose. When mine have been dormant I've decreased the watering to maybe once every 10 days to keep them the tiniest bit damp....one stayed dormant for only a couple of weeks, one for maybe 4-5 weeeks and we shall see on the third one. I personally think that the tough part is watering on almost any Amorph or Arisaema...once you have it figured out then they are not that tough, but until you do you can kill them like you put round-up on them!! I got my seed from Troy (no longer selling by the way), but you should be aware that it is not legal, from what I understand (told to me by a person who lives in Indonesia and deals with the exotic plant trade), to collect these without proper permits, as the govt. over there is starting to realize that their natural resources are being stolen....it is now almost impossible to get any plants out of Brazil because they realized the same thing a while back. I'd be interested to hear what others have to say about titanum, but you can see the obvious problem....everyone has their own regimen, but most of us other than rubbleshop have never personally flowered one of these giants and have only been growing them for a couple of years when a ton of seed flooded the market. Best of luck :o) Dan

Climate may be a factor as I an in zone 9. I don't find peat a problem, though I germinate seeds in John Innes No 1, then tranfer to a proprietry peat based compost known as "miracle grow" once about 3 months old. I don't use heat mats because Warning:- THEY CAN BE UPSET OR EVEN KILLED BY TEMPERATURES OVER 30 C (corm - leaves can take hotter)!, but then I am not in zone 6a.

I think I must have a different subspecies to you as mine never go dormant, in having no leaves, just in not actively growing for a bit. Do you know which Island Troy's seeds came from? I have seen photos of his seeds and they seem smaller than mine and to have more rounded ends. His seeds are also more cylindrcal than mine.

I don't think you can do watering by regular timings. The air humidy fluctuates too much, so the rate of drying out fluctuates to much. I always do it by feel.

Whereas you cannot legally collect the seeds yourself, many of the locals have permits to collect in areas being de-forested. This is a way many of the locals make their living. If you visit the area, you can easily find such locals and buy a lot for a small fee, which is an incredible amount of money to the local people.

If you were to try to find them yourself you would never find one in seed, loads in leaf, but none in seed, but the locals know just where they are.

Could these unsuccessful growers be cooking their corms perhaps?

Here is a link that might be useful: {{gwi:382721}}

I have been growing A. gigas now for two years and it is doing great. My corm has tripled in size. Can't say what I would be doing different from everyone else, but I probably keep it a little on the dryer side. So far I have had success also with titanum, hewettii, and decus-silvae. I think drainage is key. It seems that so many corms are found rotting in pots. Of course everyones conditions are going to be a little different but I would have to agree with Dan, keep them moist and warm.

Here is a link that might be useful: my A.gigas last year...

Hey Bryan, Looking good....keep up the good work...not sure what the problem is with mine....same potting mix as titanum and hewitii, but just no luck....a few look pretty good, but I'm going to give them away.....I know that I can not gorw them over the long haul, but hopefully Phipps can and then I can enjoy them in the future!!

Rubbleshop.....my titanum have been on a heat mat for 20 months and I can tell you that using a very accurate thermocouple I brought home from my lab the temp at the bottom of the pot was in excess of 110F....way beyond 40C....I know that they supposedly do not like that....I'm sure based not on anyone being silly enough to try it by the way!! Since mine are in a south facing window all year long they can be on a pretty tight schedule.....they do get watered roughly every 4 days in the summer ......more hours of light coming through the window....every 5 days during the winter.....so far so good, but I have taken the philosophy that razorback mentioned in a different post on Arisaema....hey if they die so what.....wasn't meant to be.....not that I want them to kick off, but after I've done my best I simply have to move on.....lets hope my latest dormant tuber comes back up in a few weeks!!

By the way....I found a place to get some Am. pygmaeus....I have 2 clones of this wonderful dwarf, but the ones I truly love like this little window Amorph I always am willing to get some more :o) Dan

Hi bluebonsai101,

It could be that zone 6a is just not the place for these Indonesian plants, even indoors for some reason.

I notice everyone having success is zone 8 or greater.

Zone 8 contributors seem to manage with difficulty, but mostly manage and zone 9 seem to find them relatively easy.

Kew is zone 8 by the way, so I think is flycatchers.

I am zone 9a, though some years we have no frost at all. Others I get a few days of -2C (28.4F) though!

I am assuming soCal (dirtface) is South California so is probably zone 9b?

Hi
Well my final decus-silvae collasped today :( Both its original leaf (on the plant since September) and latest one were rotten at the base. No sign of any seed/tuber, just mush with roots! All my Amorphophallus have died this way no matter howe careful I "thought" I had been watering and trying different compost mixes. Guess Amorphophallus are not for me...

Photo of decease-
http://homepage.ntlworld.com/wb.sherren/other/decus-silvae1.jpg

cheers

bill

Sorry to hear that flycatchers. I have never tried decus-silvae so don't know if it can be grown here here in Devon.