Hi Robert,

I'll have a stab and see if I can offer some advice. First, let me say that while I've had 13 titanum and 50 hewitii for a couple of years now I live in zone 6 and I can honestly say that my conditions and your conditions for success are likely vastly different....I never take advice from a zone 9 person too seriously since they can not imagine my climate.

OK then, I would never plant either of these in the ground. That is asking for a disaster. Second, they would not be amused by 50F for very long. They come from an area of the world that considers that temperature the equivalent of a four letter word!! Third, if your titanum came in a 1 inch pot that is just silliness. The seed on titanum are roughly 1 inch long and that pot is way too small.....pot it up immediately. I started mine in 4 inch pots and I've now potted them up into 8 inch pots....they likely will go into 10-12 inch pots at their next dormancy. I have bare-rooted all of mine over the last 2 years without any problems whatsoever. I have no fear at all in pulling one of these out of their pot and cleaning all of the old potting mix off and then potting up....this will not be possible when they get bigger, but while they are small I would rather have them in a smallish pot to keep water at a minimum!! The do not have a true dormancy like your other species (either titanum or hewitii)....they may go dormant for a week or a month at any time of year and then put up a new petiole. You should expect several petioles in succession before it ever goes dormant the first time (both species). Mine are maybe 3 feet tall now and only 3 have gone dormant in the last 2 years....one for a month and the other 2 for maybe a week or so...they were growing new petioles by the time I unpotted them. My hewitii are maybe 1 foot tall with a much more advanced looking leaf canopy. When they are dormant they should never be allowed to dry out...keep the potting mix just barely moist....not wet.....just the tiniest bit moist! I water mine when dormant perhaps once every 10 days. As for potting mix, I'm sure you will get as many concoctions as there are people that post on this thread....I would argue that you use a mix similar to someone that grows these in your neck of the woods. I personally use the mix that they use here at Phipps Conservatory for their titanums. This is pine bark, turface and charcoal (2:2:1). I water roughly every 3-4 days and use 50% or so 15-30-15 fertilizer every time I water. You will find that the titanum will get big fast....My hewitii are not fast growers, although they have lovely leaf canopies after this much time and the petioles are just spectacular....far more beautiful than titanum in my opinion....also tougher to grow so far for me!! If you live near Albert Huntington (go to Alberts Greenhouse) he can give you great advice as he is the president of the IAS and occasionally posts here. Best of luck with these :o) Dan

Thanks for the advice.

Well, it got to a bad start when I left the plant on the table to go in another room and come back to find my cat chewing off one of the four leaves! I'm sure it will make it, but I nearlly jumped out of my skin!
I think I'll grow mine in a vivarium until spring. Hopefully it doesn't outgrow it before it warms up (the vivarium is about 2 feet tall). I assume I should keep the humidity as high as I can.

Thanks,
Robert

Robert, perhaps this information will be helpful to you. I received five A. titanum seeds a few months ago and planted them in gallon pots. By the way, thanks to bluebonsai and others for a lot of good advice on how to grow it. Each seed germinated, and the first petiole of each plant reached a height of about 6 inches. A few weeks ago one plant started putting up a second petiole, which reached a height of 12 inches. (The plant now has two petioles.) All of the other plants are in various stages of putting up a second petiole. IÂm glad I planted the seeds in at least a gallon pot, because in a smaller pot the plants would have had to be potted up already.

The plants are being grown outdoors in Honolulu, where the temperature at this time of year is between about 70 degrees and 85 degrees. The plants are fertilized weekly with a mixture of a balanced orchid fertilizer, SuperThrive, and a kelp nutritional supplement. The medium is watered with this mixture, and the leaves are given a fine spray of it.

This plant seems to grow fast, so maybe you should start to make plans to expand your vivarium.

Hi Robert,

That is funny about the cat....mine have never chewed on one, but they have knocked more than one plant to the ground and completely broke a petiole off of a titanum.....fortunately it only went dormant for a month and then popped back up. The only reason I suggested a smaller pot is that it is easier to control water in a small pot....more roots and less empty space to hold water. As Hawaii says, these will grow pretty darn fast and the petioles get sort of exponentially bigger....by the time you get to a third petiole it will likely be 2.5 to 3 feet tall. Fertilizer is the real key....do not be shy in this regard. They like it, they like it a lot. Remember, just like with your others, your goal is to pull a nice big tuber out of the pot when it goes dormant. I think you will do absolutely fine with this guy. The one other thing I should mention is that mine sort of get rotated around and spend a lot of their lives sitting in a heat mat. I was shocked when I put a thermocouple under it and found that the bottom of the pots were above 100F.....well above. I would have thought that this was a stupid thing to do, but they seem to like it so far, so I'm going with it atleast until they move into bigger pots...I had to stake one of mine in the past few days because it is falling over as it produces a new petiole...nearly 3 feet tall so far....they are not planted deep enough in their 8 inch pots. Best of luck...oh, and by the way, look at the posting about the Sauromatum venosum and you will see a link to Albert Huntingtons web site...he can likely help you a lot as he is in S. California. Best of luck :o) Dan

Dan, I adhere to the same school of thought. If it's not broken, don't fix it! If they are growing fine, why tamper with it?

BTW, what is a vivarium? I am assuming it is some sort of container similar to a terrarium? Maybe taller, and not as wide?

It seems every forum I have frequented lately has spouted the merits of SuperThrive. I know it contains B-1, and many years ago, I used it on my infant begonias that I grew from seed because it was less potent than other fertilizers. Are you using it for the trace element factor?

....and congratulations on your new Titanium(s)!

Susan

Actually, I'm technically in Northern California, or more precisely the San Francisco Bay Area, which is a bit different still ... California climate is really really varied, and what works down in Southern California ( Low Cal, we like to call it ) is not the same thing that works up here.

The only advice I'd add to the excellent guidance that Dan and the others have posted is that fertilizer and well draining potting mix is key to success. Titanum is not too happy outdoors except in a sheltered area during the summer. It doesn't like the cooler, wetter weather we get up here too well, and though it doesn't die immediately, it tends to slowly decline rather than going dormant for the winter if left outdoors.

If you're an IAS member or would like to join up, the latest newsletter has an article about Bill Weaver's Amorphophallus titanum which he grew to flowering this summer after many years in his backyard greenhouse. Lots of cultural hints there...

--Albert

Here is a link that might be useful: Albert's Greenhouse