Floral Titan

It's six feet tall, it smells of rotting fish, and David Attenborough called it `truly a monster'. No wonder the botanical world is mad about a...

It is a fact of life that we are fascinated by superlatives: the biggest, the smallest, the greatest, the fastest, the oldest, the rarest, the strangest. Think of the perennial success of the Guinness Book of Records or, come to that, the buzz currently being generated in botanical circles by the imminent flowering - today or tomorrow - of the world's largest flower, the Titan Arum, at the Huntington Botanical Gardens in San Marino, California. Although this is the 11th time that the Titan Arum (botanical name Amorphophallus titanum), a tropical plant from the rainforests of Sumatra in Indonesia, has flowered in the United States, it is the first time outside Indonesia that it has done so without the shelter of glass. So the excitement in California is intense, with visitor attendance at the botanical gardens up by 20 per cent, and hundreds more people ringing the hotline each day to check the plant's progress.

The fuss is understandable, too, for the mature flower will certainly be a sight to behold - more than 6ft tall and perhaps as much as 4ft in diameter - and will last a mere three or four days. But it is not just size that attracts the attention of botanists, who also have an irredeemable fascination with the weird. For the Titan Arum is not simply a chrysanthemum or snowdrop writ large, but something very strange and wonderful indeed.

Although it's related to our Easter arum lily, the Titan Arum's aspect is altogether more awe-inspiring. The flower, held on a short stalk, consists of a "spathe", approximating to a single giant petal, that encloses a central fleshy column called a "spadix", which can grow to a height of 10ft and bears tiny flowers at its base, hidden by the spathe.

Strictly speaking, it isn't a "true" flower at all, but an "inflorescence", or collection of flowers, which emerges at the end of a long dormant period, growing up to 4ins a day over a period of about three weeks. As the pale yellow spike reaches maturity, the spathe opens out to form a vast, ribbed, frilly-edged trumpet, greenish on the outside but deep maroon within.

And there's no getting away from it: the first thing that the mature spadix calls to mind for most people is its resemblance to an enormous phallus. Certainly Blume, the botanist who first described the family, did not shrink away from scientific exactitude, calling it Amorphophallus, "amorphos", which means "shapeless" or "deformed".

In the forests of Sumatra, the single umbrella-type leaf can reach 15ft across, on top of a 20ft stem, while the underground tuber from which first the flower, and later the leaf, emerges, can be so heavy that it requires two men to pick it up. Sumatran legend has it that the plant will even eat its grower, hence the local name of "corpse flower". No wonder David Attenborough, when he was confronted by the Titan Arum in the wild, described it as "truly a monster".

But if the sight is startling, and not a little disturbing, the experience is made more memorable still by the extraordinary smell: at the moment when the Titan Arum's pollen is receptive, the spadix actually heats up from within and gives off a powerfully malodorous stench of rotting fish - perfect for attracting the carrion beetles and "sweat bees" which it needs to pollinate it. Indeed, when the Titan Arum flowered at Kew in 1891, an artist by the name of Miss Smith was asked to draw it, but she suffered "prolonged martyrdom that terminated in illness" as a result.

In the New York Botanic Gardens in 1937, the Titan Arum made onlookers' eyes water, but that did not stop photographers from "half a dozen motion- picture companies" setting up their equipment to capture the moment. It was even declared the official flower of the Bronx. "Its tremendous size shall be symbolic of the largest and fastest-growing borough of the City of New York," announced the borough president, adding with some understatement, "there are many other sweeter-smelling flowers but none as large and distinctive."

Amorphophallus titanum was first documented by the Italian botanist Dr Odoardo Beccari in 1878 - an event now regarded as one of the greatest highlights of natural-history exploration, according to the aroid expert, Deni Bown. Dr Beccari wrote at the time to a friend: "The single flower... with the tuber... form together so ponderous a mass, that for the purpose of transporting it, it had to be lashed to a long pole, the ends of which were placed on the shoulders of two men. To give an idea of the size of this gigantic flower, it is enough to say that a man standing upright can barely reach the top of the spadix with his hand, which occupies the centre of the flower, and that with open arms he can scarcely reach halfway round the circumference of the funnel-shaped spathe."

Dr Beccari duly sent back seeds to Europe, with one plant ending up at Kew Gardens, where it was so skilfully cultivated under glass that it flowered just 10 years later, in 1889. By that time, the tuber weighed in at a mighty 57lbs, and the inflorescence measured 6ft 9ins. Dr Beccari himself was so thrilled that he commissioned a life-size painting of the plant, which he gave to Kew as a tribute to their achievement. Measuring 18ft by 15ft 6ins, this remarkable artwork hung for a time in one of the museum buildings, before disappearing mysteriously from view.

In the 120 years since Dr Beccari's discovery, botanists' fascination with the Titan Arum has undoubtedly been heightened by its comparative rarity and the remoteness of its natural home. To locate a specimen in the forests of Sumatra has never been an easy matter - and nowadays, though it is not strictly speaking endangered, its habitat, secondary forest, is under threat from logging.

Away from the wild, however, its future is more assured. Although Huntington Botanical Gardens can boast that this is the first time that the plant has flowered in California, it has bloomed elsewhere in the United States. In Europe, in addition to Kew, it has also made visitors wrinkle their noses in Bonn and Leiden. Each time it flowers, botanists and gardeners discover more and more about its characteristics and cultivation requirements, and there may come a time when its flowering seems, if not exactly commonplace, then at least no longer cause for international comment.

The irony is that despite the hype, botanists are not even in full agreement that the Titan Arum is the largest inflorescence in the world. There is another member of this extraordinary family, Amorphophallus gigas, which has a slenderer flower that grows on a 10ft stalk. And the much better- known Rafflesia arnoldii, which also comes from Sumatra, is the world's largest true flower.

But who cares? This flowering Titan has come to act as a symbol of the awesome variety of plants in tropical forests. It is worth making a stink to help preserve that.

If you would like to follow the progress of the Titan Arum at Huntington Library, Art Collection and Botanical Gardens, ring the Huntington Flower Hotline on 001-800-200-5566, or visit their website at www.huntington.org