The Stellenbosch University Botanical Garden has a number of glasshouses containing various weird and wonderful flowers, shrubs and trees that are not adapted to the Western Cape’s climate. Two glasshouses mimic an arid environment, hot and devoid of rain. But it was one of the tropical glasshouses that had the most foot traffic in the past week.

Resembling and feeling like a hot and sweaty tropical forest, it housed a titan arum or “corpse flower” in a unique and rare bloom. 

“It was around 1,000 to 2,000 people per day through most of that week of people coming specifically to see the corpse flower,” says Donovan Kirkwood, curator at the botanical gardens. 

It smelled like…

The titan arum is endemic to the Sumatran rainforest and only blooms every five to seven years. It is this bloom that gives the plant its uniquely morbid nickname: it has evolved to attract pollinators that would ordinarily lay their eggs on the corpse of a dead animal, mimicking the stench when in bloom.

The plant reached full bloom on Tuesday, 13 December, at a full height of 1.5m. 

A Titan Arum or ‘Corpse Flower’ is set to undergo a rare bloom at the Stellenbosch University Botanical Gardens. Photo: Téa Bell.Photo:Jamie Venter

“It wasn’t quite as intense or as bad-smelling as we expected, except late in the evening once the glasshouse was closed,” says Kirkwood. “But then we are also used to bad-smelling flowers.

“The corpse flower was actually more like a mix of faeces and smelly cheese to my nose than dead animal.” 

Read in Daily Maverick: “Now this is worth making a stink about – southern Africa’s only ‘corpse flower’ to bloom this weekend”

Although the plant is adapted to smell during bloom, this plant did not attract swarms of flies. 

“There is still some doubt about exactly which species pollinate this plant in its native Sumatra, so it may be that the scents target a specific set of insects,” explains Kirkwood. 

But, “more obviously, of course, we are in the middle of town and the plant is inside a glasshouse, making it difficult for flies to find their way to it anyway”.

Corpse bride

The titan arum is the largest single inflorescence of any plant in the world. An inflorescence is when many small flowers cluster together on a single plant, and on the corpse flower this is on a central spike, or spadix.

There is a “bunch of girl flowers at the bottom and a section of boy flowers above that, with the tip of the spike devoted to being really stinky”, says Kirkwood. 

In nature the titan arum does not self-pollinate since the female flowers mature first and are no longer receptive by the time the male pollen is released, explains Kirkwood. 

“We tried an experimental method to bypass this limitation by crushing immature anthers (the male reproductive organs in plants) to hopefully release some viable pollen.” 

Read in Daily Maverick: “The secret ultraviolet colours of sunflowers attract pollinators and preserve water”

If successful the flower will collapse but develop into a fruit that looks similar to fruits produced by the related “delicious monster” plant. “If unsuccessful the flower will just wither completely and the plant will go dormant for a while before producing a single giant leaf,” says Kirkwood.

“We have botanical garden partners who have requested pollen and that will be shared with them.” 

It will be years before the plant is expected to bloom again, says Kirkwood. But, “fortunately many new visitors discovered the rest of the delights of the garden and stayed a few hours”. DM/OBP