One of gardeners’ favourite exotic plants is being wiped out by an evil-smelling frothy-orange slime.

Wisley’s Torbay palm was felled (copyright: RHS)

Royal Horticultural Society experts have been inundated with “hundreds” of enquiries from gardeners whose dying cordyline palms are displaying unusual symptoms.

The cause has been identified as slime flux: a bacterial infection that’s attacked palms for the first time in the UK, following the coldest December in 100 years.

Slime flux usually affects clematis, but it has now spread to cordylines (commonly known as Torbay palms).

“There have been strange goings on,” said senior horticultural advisor at RHS Garden Wisley, Helen Bostock.

“We’ve had hundreds of calls about pinky/orange slime on cordylines.

“It has a horrible smell of stale vomit and oozes colourful frothy stuff. It’s like something out of the X-Files.” Bostock explained.

The disease has even hit the prestigious RHS garden where a Torbay palm had to be chopped down.

“You had to be only three feet away, or downwind of it to know there was a problem,” Bostock added, referring to the stink.

Cordylines, which originate from south-east Asia, are hardy down to ­minus 5°C (23°F).

Last winter, parts of the UK hit ­minus 22°C (-8°F). Frost led to tissue damage and these wounds allowed bacterial slime flux to infect palms.

Graham Clarke, a horticultural expert with Amateur Gardening magazine, said: “We have had an unprecedented number of enquiries about dead or dying cordylines this spring.

Infected palms ooze smelly slime (credit: RHS)

“The slime flux manifests itself in very serious cases, but even without this symptom, millions of cordylines have been obliterated following the incredibly cold winter.

“Even experienced gardeners, who wrap cordylines up for winter, have suffered huge losses.

“Ten years ago there was a national shortage of cordylines following regular recommendations on TV makeover shows like Ground Force.

“This year, demand will be high again as gardeners seek to replace dead plants,” Clarke added.

To make matters worse, there is no chemical or organic control for slime flux.

Infected stems must be hard-pruned back to healthy wood. Where the main trunk is diseased it will need to be chopped back to ground level. Cordylines will occasionally re-grow.

Bob Flowerdew, a panellist on BBC Radio Four’s Gardeners’ Question Time, said: “From my own observations, there are hardly any cordylines with live tops left in most of the UK, other than a few down on the Torbay Riviera and similar protected spots.

“This is due to the cold winter, while the slime flux is more a sign of their sick state from the cold. They may re-grow from roots,” Flowerdew added.