Visitors flocking to Sidmouth which is famous for its award-winning blooms are being reduced to tears by an infestation of wild onions.
The tiny plants resemble a meadow of pretty white wildflowers but are actually Allium triquetrum, part of the same family as onions and garlic.
They give off a potent pong which is wafting across Sidmouth forcing disgusted tourists and locals to hold their noses.
Worse still, the smelly interlopers are actually wiping out native species like the bluebells, a distant cousin, that carpet much of the town’s pretty lawns and promenades.
Sidmouth’s spectacular, fragrant blooms attract holidaymakers from across the globe and have won numerous awards.
One regular visitor, retired banker Keith Sutton, 69, was so besotted with its daffodils, snowdrops, bluebells and crocuses that he bequeathed his £2.3 million fortune to civic leaders after his death in 2007.
Mr Sutton stipulated that the money could only be spent preserving the town’s charm and left instructions for one million bulbs to be planted in his memory.
But local horticulturist Lois Kelly warned, however, that visitors to Sidmouth and its picturesque Byes Riverside Park will now have to contend with the stench of onion.
She said the pungent plants have taken hold in several areas and are threatening to “annihilate” bluebells.
Lois said: “They are about the same size and have invaded the Byes and other parts of Sidmouth.
“They are not white bells, they are wild onion and very aggressively invasive.
“When you walk by on a warm day they smell of onion, or just break a leaf stalk and you can smell it.
“If you have them in your garden and don’t want to be overrun or have your bluebells annihilated, then dig them up – bulb and all.
“And don’t put them into your compost but into a black bag and leave them to rot on their own.”
District council chiefs are deciding what to do about the onions, which can be seen in areas that were previously treated for an infestation of knotweed.
A spokesman for East Devon District Council, which maintains the byes and several other green areas, said: “The bank did have an infestation of Japanese knotweed until recently.
“It has been treated progressively over the last five to six years and it looks like the wild onions have grown in to take over the space.
“Any bluebells that were there were either choked out by the knotweed or succumbed to the herbicide used to control it.”
Allium triquetrum is a bulbous flowering plant in the genus Allium – the same family as onions and garlic.
It is normally native to the south-western Europe and north-western Africa, but has also been introduced to British Isles, New Zealand, Australia and the US.
Common names include wild garlic, which is also used for many Allium species, and the three-cornered leek.
All parts of the plant, from the bulb to the flowers, are edible either raw or cooked and are said to have a subtle flavour like leek or spring onion.