Its bizarre appearance and sheer size have long attracted curious visitors and avid gardeners alike.

One of two Titan Arum plants due to bloom at Kew Gardens in the next couple of days. [China Daily]

But anyone wanting to see this Titan Arum flower would be wise to keep their distance this weekend. For when it blooms – which experts predict should occur in the next few days – it will release not the fragrant scent of most flowers, but a revolting stench rather like rotting flesh.

And to make matters worse, two Arums are due to flower at the same time – a first in Kew Gardens' 250-year history. The plant – which is indigenous to Indonesia and also goes by the name "the corpse flowe"' – blooms just once every six or seven years.

Twelve of them are housed in Kew's Princess of Wales Conservatory among hundreds of other tropical plants. At the Arum's base is an outer layer of grooved leaves, which open to form a bell-shaped cup or deep red "spathe."

A band of cream flowers circles the base of the stem or "spadix,"

which sits on a ring of larger, pink flowers. When the plants are ready to pollinate, the spadix heats up to release a pungent smell, which lasts for about three days. Flesh-eating beetles, attracted by the "fragrance," crawl into the open cup while bees and other insects flock to its coloured base.

Once inside, pollen is transferred from the flower to the insects, which become trapped in the chamber.

The spathe then withers to allow the pollen-covered insects to escape and pollinate other Arums in the rainforest, or in this case the greenhouse. Phil Griffiths, Kew Gardens' conservatory co-ordinator, said: "Most people miss the actual flowering when the smell has dissipated.

"The smell is strong and pungent, as if you were in the tropics and had passed something dead and rotting by the side of the road. It comes at you in waves – at first you can't really smell anything, then it hits you."

He added that the largest Arums at the gardens weigh about 200lb (90kg) and grow at a staggering rate of a quarter of an inch an hour. Four members of staff are drafted in to help when any Arum needs repotting.

It guzzles liquid fertiliser and potassium each week to keep up its strength while bedded in roomy surroundings.

Sir David Attenborough, who invented the name Titan Arum, was the first to capture its flowering on film for his BBC TV series The Private Life of Plants.

He dropped the plant's original name – Amorphophallus – perhaps because of the reference to male genitalia.

(China Daily via agencies, April 28, 2009)