This month’s Greenspace looks at a rather curiously named genus of plant, the Amorphophallus, or ‘misshapen penis’.
The biggest seed in the plant world is the coco-de-mer (Lodoicea maldivica), the biggest fruit is pumpkin (Cucurbita pepo), the biggest flower is Rafflesia arnoldii (commonly called the corpse flower), the biggest branched inflorescence (or flower structure) is the talipot palm (Corypha umbraculifera), the tallest unbranched inflorescence is Amorphophallus gigas and the biggest unbranched inflorescence is the titan arum (Amorphophallus titanum). These qualifications of superiority are de rigeur for botanists (although perhaps rather pedantic and irritating for non-botanists). That authoritative source, The Guinness Book of Records, lists the titan arum as the world’s largest flower and gives Bonn Botanic Gardens’ 2008 bloom the record with a height of 3.06 metres. Amorphophallus titanum is native to the rainforests of western Sumatra and is enough of a celebrity to attract a crowd – as shown with recent flowerings at Mount Lofty and Adelaide Botanic Gardens. My favourite photos of David Attenborough show him in an ecstatic state posing variously with this species in Sumatra. Somewhat confusingly, it’s referred to as the corpse flower (along with Rafflesia), or, less confusingly, as the titan arum. I used to imagine that the titan arum’s botanical name meant ‘not shaped like a penis’ but it translates more accurately as ‘a misshapen penis’. The inflorescence (or flower structure) includes the spadix, the yellowish flowering spike that provides the simile with a misshapen penis, and the spathe, the maroon leaf-like structure that surrounds the spadix. The flowers themselves are tiny structures forming rings around the spadix within the protection of the enveloping spathe. The renowned nauseating smell of the inflorescence is most evident as first the female, and a day later, the male flowers reach maturity. The foetid stench is supposed to attract flies as pollinators although Wilbert Hetterscheid, the world authority on Amorphophallus, suggests carrion beetles are more likely responsible for pollination. If you think about it, our uncertainty here, in relation to one of the world’s most spectacular and charismatic flowers, is quite astonishing and again underscores our remarkable ignorance of the plant world. The titan arum is declining in the wild as a result of deforestation and we still barely understand its ecology. The titan arum was recorded for science by Florentine botanist Odoardo Beccari. Beccari saw a plant in leaf in Atjer Mantior (Aceh) on August 6, 1878, and a flowering plant on September 5 that year (the tuber throws a single leaf or a flower, but not both at the same time). His report in the Gardener’s Chronicle in November 1878 named the remarkable discovery for science as Conophallus titanium, which translates best as ‘the cone-shaped titanic penis’. Pisan colleague Giovanni Arcangeli saw the titan arum more appropriately placed with the misshapen penises characteristic of Amorphophallus and published the current name in 1879. The titan arum first flowered in cultivation in the Royal Botanic Gardens, Kew, in 1889. The flower is certainly spectacular but the titan arum is also worth growing for the glorious leaves that can reach 6 m in height. The tuber itself is exceptional and can reach in excess of 100 kg making it the largest in the plant kingdom. Tubers, being buried and rather shapeless, tend not to get the same adulation as flowers (unless they’re crop plants like potatoes and we’re eating them). Amorphophallus includes around 170 species with extraordinary flower shapes, colours and scents as well as the species with titanic sizes. Many of the co-geners for the titan arum are beautiful and remarkable. As we’ve seen, the inflorescence on A. gigas exceeds the height of the titan arum but is slenderer and considered rather less spectacular. Still, there are fine photos of this species accompanied by a very excited David Attenborough and amorphophallusaphile Wilbert Hetterscheid. A few species of Amorphophallus are cultivated as food plants. A. konjac is cultivated in India, China, Japan and Korea for its starchy tubers which are used to make an edible flour or jelly. A. abyssinicus, A. albus and A. paeoniifolius are also cultivated as crop vegetables but require significant preparation. The voodoo lily (A. bulbifer), native to India and Sri Lanka, is more common in ornamental plant cultivation and distinguishes itself with a particularly appalling stench. For first-hand experience keep an eye on Adelaide and Mount Lofty Botanic Gardens flowerings. Nurseryman Matt Coulter’s passion, knowledge, commitment and international perspective, and the support of the gardens’ team and volunteers, have been realised in the remarkable titan arum collection at Mount Lofty. Perhaps you can even get to Sumatra and join an ecotourism adventure to track down both the largest flower, Rafflesia arnoldii, and the largest inflorescence, Amorphophallus titanium, in the Batang Palupuh reserve near Bukittinggii in West Sumatra. If flowering specimens aren’t found within the reserve, guides can often lead visitors to view plants in surrounding forests within a few days. For botanical detail you can’t go past Wilbert Hetterscheid’s and Stephen Ittenbach’s 1996 Everything you always wanted to know about Amorphophallus, but were afraid to stick your nose into!!!!! published in the International Aroid Society journal. @StephenJForbes Image: Amorphophallus gigas. Image courtesy Wilbert Hetterscheid ©.