Standing alone in a glass conservatory at the Adelaide Botanic Garden is the Titan Arum, a two metre tall floral beast that has Adelaide holding its nose in anticipation.
If you don’t recognise the name, perhaps you’ll know this plant by its other, more evocative moniker; the “corpse flower” is a rare and notoriously putrid-smelling plant from the tropical jungles of Sumatra.
The Botanic Gardens and State Herbarium is building a reputation as a global leader in the propagation of this legendary plant, which takes ten years to produce a single flowering structure that lasts for just 48 hours. But what looks like a single flower is actually a collection of hundreds of tiny flowers called an inflorescence, which emit a scent of rotting flesh. It’s this potent odour that has crowds gathering in their thousands to witness one of the rarest botanical events in the world.
The Botanic Gardens’ collection is the largest in Australia and one of the most significant in the world. And it all started with just three seeds. In 2006, the Botanic Gardens received a generous gift of three Titan Arum seeds from private donors, and a team of horticultural experts gathered to nurture and grow them in a heated glasshouse at the Botanic Gardens Nursery. As the young plants flourished, the Botanic Gardens began its pivotal role in the conservation of the Titan Arum.
Due to deforestation and habitat loss in its native Sumatra, the species is now listed as vulnerable on the IUCN Red List of Threatened Plants. This threat has prompted botanic gardens and environmental organisations around the world to research and conserve this gem of the plant kingdom. The Botanic Gardens and State Herbarium is part of this international effort and is working with research partners to glean new insights into one of the world’s most difficult to grow plants.
The cultivation of Titan Arum is particularly challenging due to the plant’s complex growth cycle, and it can take years for a new seed to develop. The science program at the Botanic Gardens and State Herbarium of South Australia is helping to develop new techniques and using that research to help save the species.
The propagation of Titan Arum has been particularly successful. In 2013, nursery staff undertook trials to assess the viability of using leaf cuttings to propagate more plants, a technique that had previously been reported but rarely published. After many trials, the team eventually found two successful techniques.
These techniques, known simply as horizontal and vertical, involve taking a small branch of the mother plant. Leaves are selectively pruned before a special hormone is applied to the stem, which encourages the plant to root. The technique is elegant in its simplicity and has allowed the Botanic Gardens to significantly expand its collection and solidify the institution’s global reputation as corpse flower experts.
This success has been shared widely with the botanical community, enabling further research to uncover Titan Arum’s secrets. And while that community holds its collective breath for the third public viewing of the flower, which is expected this week, the Botanic Gardens has enjoyed three more flowerings in the confines of its nursery. These more private affairs provide an opportunity to conduct in-depth scientific analysis of the plants.
This week’s blooming, however, is a mixture of business and pleasure. While Adelaide’s eyes – and noses – will be fixed on the corpse flower, the Botanic Gardens will be working with an international team of researchers to gain a deeper understanding of the flower’s biology.
Botanists from the University of Adelaide will be bringing high-tech thermal imaging to measure the heat output during flowering, while DNA analysis will be undertaken in collaboration with the Chicago Botanic Garden and Botanic Gardens Conservation International.
This international outlook is indicative of the Botanic Gardens and State Herbarium’s forward-looking approach and its commitment to the conservation of the natural world for future generations.
In coming years, the staff will continue to gather information and hone their horticultural skills in the hopes of turning this rare occurrence into a common one. And the Titan Arum is not alone. The team at the Botanic Gardens is also working to help preserve a range of South Australia’s threatened plant species as part of their mission to safeguard our flora for future generations.
The corpse flower is located in the Adelaide Botanic Garden’s Bicentennial Conservatory and is expected to bloom later this week.