Variety Pedunculatum


Variety pedunculatum is relatively restricted in distribution. It exists at the western edge of the realm of its more expansive neighbour, variety boreale . . . almost like an add-on that did not go to plan. It inhabits a north to south distance of around 100 kms but only has an east to west span of about 20 kms as a rough average. All of this strip existence happens on the western watershed of the Atherton Tableland. The central point of this distribution is roughly west of Atherton and Herberton townships. See distribution map in the main menu.

Vegetative Characteristics:

If you are not familiar with var. pedunculatum it certainly will not take you long to catch on. It is a dwarf form of D. speciosum. Bulb size varies tremendously but even the more robust ones are still dwarfed to a degree. Some mixing with the genes of nearby var. boreale would seem likely and may influence this variability in size. The two are quite individual varieties however and intermingling is no doubt quite rare.

At its smallest size, var. pedunculatum could be mature and capable of flowering when only as large as the thumb of woman. At other locations, some bulbs will occasionally be seen approaching the size of a large cucumber. I have seen bulbs around 250 mms long and 40 mms wide. This is exceptional however. The size is no doubt related to the nutrient supply combined with available moisture.

Plants growing on the bottom of higher rock walls and cliffs perform better because of the catchment that traps leaf litter (food) and water and releases it over longer time spans. A plant that has taken root on the top of a rock will be struggling to attain any size. This is not shattering new knowledge by any means. But it is particularly relevant in the case of var. pedunculatum.

Because of the influence of the tropical wet and dry seasons, var. pedunculatum willl need to survive with no rain at all for months on end. Combine this with its already hostile environment, even when times are good, and you can see why this variety has dwarfed itself.

No doubt in an effort to conserve meagre water supplies through the dry season, var. pedunculatum has evolved thickish leaves that are quite upright. Being upright no doubt reduces the exposure to the sun and conserves moisture in the thick leaves, which are also quite dwarfed. Moisture is squirreled away in other words. Bending the leaf of a wild plant will lead to it snapping in no uncertain way. Leaves and bulbs on plants in exposed sunny spots often have purple to maroon colouration. In the case of var. pedunculatum this is therefore a common phenomenon.

Floral Characteristics:

Variety pedunculatum is so named because its raceme sports a very long peduncle. The peduncle is that part of the flowering stem between the leaf axil and the first flower up the stem. Just to fill you in, the part of the stem from the base flower to the terminal flower is known as the rachis. (This is fascinating stuff, what do you reckon?)

The peduncle on var. pedunculatum varies from a half to two thirds of the raceme. In other words, just over half of the raceme will have no flowers at all. Raceme length will vary according to seasons and conditions, but they can be up around 750mms. On the typical plant in the bush however, the length is likely to be less than 400mms and as short as 200mms. The racemes are frequently upright but occasionally gently arching but never pendulous.

Flower colour is nearly always an off white or cream variation. Light yellow is also seen. But some wonderful deep yellow colours turn up from time to time. I have seen a few hundred specimens flowering in the wilds over two separate trips and only seen one that I would call a strong yellow. Good whites are likely around as well but I cannot recall having seen any in the bush.

Shape is rather uniform across this variety. I have not noticed any variations worth mentioning. Blooms are close to circular in shape if you imagine a circle drawn around the outside tips of the segments. Size will vary but once again this is highly dependent on the conditions at the time of flowering. Maximum size is perhaps 30mms but commonly less.

General Comments:

It might surprise a few of you to learn that var. pedunculatum is not really all that scarce. However, not a lot of people have ever actually seen it in situ at all. In the 1990s I had searched for it over several excursions and ended up a blank. It was not until 2006 that I was taken to a location where I would never have even bothered exploring. Even as we walked down an old track through a treeless and burnt out hillside, I had my reservations that maybe I was having my leg pulled by the mongrels leading me.

Sure enough, the odd specimen starting to appear amidst the rocky surrounds and dubious shelter thereof. A few tufts of shrubbery were sufficient to attract the diminutive speciosums slowly materialising. If it had not been flowering season, many of the plants would have remained invisible, to my eyes at least. Even in flower they were nearly invisible. I unknowingly walked past a few clumps only metres from me. Not my normal form at all I must inform you!

But this describes well the problems that you face when searching out these dwarf pedunculatums in habitat totally removed from the normal understanding of D. speciosum. Specimens were appearing steadily as my comprehension of the location sharpened during the next few hours. In actual fact the plants were more abundant then what I had thought only a short time before. What a great day of learning this had been . . .

On a subsequent trip on my own some years after being guided into that first location, I was successful in locating another colony without assistance. Once again it was a case of a spot I might very well have walked right past in years gone by. If you want to see var. pedunculatum in the wild, you might have to change your whole idea on where to find D. speciosum in the first place. I sure did.

Despite all the indicators about the chosen habitat for var. pedunculatum above, when grown in cultivation, it actually demands something more traditional . . . and it responds well to kinder treatment. The bulbs will fatten up and grow longer, and the leaves will soften up to a degree and more or less take on the appearance of a more civilised speciosum.

It is actually nearly impossible to grow var. pedunculatum the way it grows in the wild. You would have to put in on a rock under a gum tree and hardly water the thing at all. It should always be remembered that var. pedunculatum chooses to grow where it does, in seemingly inhospitable environs just a km or two away from rainforests and wet creeks with plenty of rock face to support it. But there is no var. pedunculatum there! It does not like it like that soft, lazy stuff. It wants to live in the harsh country and that is what it does.

This next bit of wisdom will no doubt shock a few growers out there. But I am not a real lover of var. pedunculatum. I grow it because it is unusual and tough, and because it is a D. speciosum in the first place. And I am a lover of D. speciosum in all its forms and ways.

Its flowers are not particularly showy and really add nothing too glamorous to other speciosums when line breeding them. The same goes for its use in hybrids. Breeders have used it extensively for two main reasons. Most obvious of all is the dwarfness. You can get the speciosum influence happening, but on the dumpier bulbs. That is a fine reason.

The other reason is that the long peduncle can lift flowers, be it in speciosums or in hybrids, above the leaves of the plant underneath it. As the judging standards suggest, it is best to avoid crowded flowers down in the leaves. And that is so true. Var. pedunculatum can overcome this problem. I like var. pedunculatum, so don’t misunderstand me. I just like some of the other varieties a bit more!

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