Amorphophallus are a group of striking, very unusual plants found growing on forest floors in tropical to temperate regions of Asia, Africa and Indonesia. Some are considered almost hardy in very sheltered gardens in the UK but most benefit from additional heat and winter protection. Many can be placed outdoors in summer in a protected, warm and shady position whilst some require year round glasshouse or conservatory conditions.
They are fascinating plants with one species from Sumatra, Amorphophallus titan, producing a dramatic flower spathe up to 3m in height! You’d think this would be considered perhaps the largest flower in the world, which on appearance it surely is. But each spathe has a central spike which holds hundreds of tiny individual flowers, making the bloom typically a collection of flowers. If you’re wondering, the largest flower in the world is also from Sumatra, Rafflesia, a parasitic plant that produces a single flower almost a metre across!
For us gardeners here, Amorphophallus can be a challenge to grow albeit a very rewarding one given their oddball curiosity value with striking flower spathes and often dramatic Giraffe-neck-like stems holding large attractively composed leaves ; some narrow and Falmouth feather-like, others broad like an umbrella.
The reason we love them here at Big Plant is that despite their origin, once you understand their cultivation requirements it is possible to grow them quite happily. They grow from an underground corm which can be large, over a dinner plate size in some species. All species have a dormant period when all growth retreats to the corm. This is convenient as it allows us to overwinter them easily in a frost-free location. I would suggest for most of us, container cultivation is the best bet. Use a container large enough to allow the corm to double in size each season or at least produce offsets, a good way of propagating them. They love rich humus and organic compost which needs to be free draining. I would add good garden compost or leaf mulch to a proper multi-purpose compost, ideally choosing an ericaceous compost.
The corms can be dry-stored in winter in a cool, minimum of 10 degrees C, dark spot, then potted up in late spring positioning the corm at least as deep as the thickness of the corm in the container (usually 3-10cm deep). Then depending on the species place them in a warm spot indoors until growth appears, keeping the compost just moist. Mature corms usually produce a flower before the main leaf stem occurs, some do this at the same time.
As the plant develops, a gentle feed of fertiliser such as seaweed extract can be applied throughout until growth slows. The flowering spathe at the beginning of the season is spectacular, it may take a few years to achieve a flowering sized corm. Just be aware, as I’m sure you are if you had read this so far, the spathe containing the flowers in in nature, pollinated by beetles or flies so rather than producing a sweet perfume, most Amorphophallus produce a significant pong for a day or two!
If your corm is still a youngster, and most are when you buy them, don’t despair that you are missing out on the pong or the wonderful flowering spathe. The long, often a metre or more stem which holds the compound figured leaf is often patterned dramatically in the classic ‘Giraffe neck-like’ pattern. The leaf too is striking, usually wonderfully architectural and sometimes otherworldly.
So in summary a fertile free draining compost is best, ideally grow in a container.
Some additional warmth is required in spring and perhaps autumn.
The corm can be overwintered dry in a cool position above 10 degrees C.
Some species can be grown outdoors in a dappled shade position during warmer months.
A few species can be grown outdoors in very mild locations given shelter and free draining soil.
For any further information about your Corpse Flower, please either call us on 01903 891466 or email us at info@bigplantnursery.co.uk and we will be glad to help.