Concerns over my Amorphophallus

I am not sure which one it is, But I have had it 4 years, It has bloomed all 4 years but each year it has taken longer and has more sets of leavesbefore it blooms. The first year it bloomed with no leaves and then the next leaves, And this year it has several leaves before it ever sent up a bloom chute, Also it always dies back to the ground after it blooms?

Am I slowly killing it, It is in the ground in a white ploy topped GH. Is it not getting enough Sun, fertilizer?

Thanks for any help you can provide.
Pheadra

This is from this morning. The leaves seem so fragile, one is already bent over and dying

The first thing is that an individual tuber will usually bloom only and not throw leaves the same year. Mine alternate; one year a bloom, next year leaves, etc. You may very well have more than one tuber in the ground, with some producing leaves and one blooming.

Next, they need a good fertilization regime in order to bloom reliably. The leaves on yours look awfully pale, so i'm sure that they are hungry. What kind of fertilization regime are yours on?

LariAnn
Aroidia Research

Thank you LariAnn, It has been getting Miracle gro once a month , Should we be feeding it something else.

I suggest once per week fertilization; you can do it with Miracle Gro but you'll need three types. The regular is for this time of year, in midsummer you switch to something with all the numbers the same, like 14-14-14, and in fall switch again to the bloom booster, 15-30-15, or equivalent.

I use controlled release granular; spring is 20-6-12, midsummer is 14-14-14 and fall is 14-26-6. You need the high phosphorus later in the season to build up tuber size and promote blooming the following year.

I see a lot of mulch there; that mulch might be eating up all the nitrogen, which would explain the yellowed leaves. I would thin out the mulch around your amorph and make sure the fert sinks in below, into the soil a ways. Amorph tubers are re-formed every year and they end up lower in the ground each year as well.

LariAnn
Aroidia Research

Thank you, I had no idea the mulch would harm our plants, We have a large Gh that we turned into a tropical garden, I have noticed that some of the plants are paler than they should be.
What can I get that will fertlize inside the Gh for an odd collection of plants.
We have always used miracle gro as the only fertilizer, We have a new bottle of superthirve, Will that help things until I can find the controlled release granular; that you have recommended. "spring is 20-6-12, midsummer is 14-14-14 and fall is 14-26-6".

Miracle Gro works well, but there are several kinds you can get. You can use a combo of Miracle Gro and controlled release as well; one of the best controlled release ferts is Dynamite, but check the analysis (the three numbers) to make sure you're getting what you need. I think they make an 18-18-18 which is good for midsummer application on all tuberous plants that go dormant in winter. The Miracle Gro bloom booster, 15-30-15, is fine for Fall use if you can't find the 14-26-6 or equivalent.

Superthrive is great and I use it all the time, but it is not a fertilizer and won't help with the pale leaves. A mix of plants is always a challenge, but the Miracle Gro is a good fertilizer to start with. Some plants just need more than what you are giving them (1x/wk vs. 1x/month).

LariAnn Thank you, I will get the items you have suggested right away,
and I will start a weekly regime, monthly and seasonal.
Pheadra

That looks like a Drancunculus vulgaris, it might be happier outside in a bit of shade. It does have a bloom and leaves at the same time, unlike Amorphophallus. You can google it to see how other people grow it.

Hello Pheadra,
I also think that it is D. vulgaris. These prefer semi shade and are likely to be unhappy at heated greenhouse temperatures. I grow mine is large tubs and dig them every year, storing them bare in the house during their summer dormant period as it is much too hot here for them to be comfortable out of doors when they are dormant. Well fed tubers will grow dramatically in size each year my largest is now approaching the size of two clenched fists. the annual digging also allows me to give them fresh nutrient rich potting mix for each season. The bigger the tuber gets, the taller the stem will be and the larger the flower will get. I was at a plant sale last year and saw a flower which was well over 4 feet long from base to spathe tip, I can't begin to think how large the tuber would be to produce a flower of that size!

Here is link to my journal entry fro this plant: http://davesgarden.com/tools/journal/viewentry.php?rid=159401
and here is a link to the Plant Files entry: http://davesgarden.com/guides/pf/go/2034/

I hope you will find this information useful,

Ciao, Kaelkitty.

Hi, on most plants, yellowing of the leaves is caused by chlorosis, this is brought about by insuficient iron. A spray with iron chelate or iron sulphate at no more than the recommended rate should correct it within a week. ,,,,Bob.