A rare Mexican plant which flowers once in its lifetime has blossomed, smashing a glasshouse roof in the process.
Scientists at Bangor University waited 28 years to see the century plant, from which tequila can be made, bloom.
A curator, who had planted the seed as a student in 1979, has spoken of his "shock" when he discovered it had sprouted a 1.6m (5ft) flower stalk.
He compared the plant, now 6.2m (20ft) tall, to "some monstrous creation from the Little Shop of Horrors".
Nigel Brown recalled how he had planted a small specimen of agave americana (its official name) on a cactus mound 28 years ago.
He said: "It has grown steadily to dominate the south-eastern corner of the display, its crown of rather untidy but impressive succulent leaves spewing out across the gravel like some monstrous creation from the Little Shop of Horrors."
When he planted it, the original intention was to see if it could survive the British weather. he explained.
But, aside from tending it occasionally, they had "pretty much forgot about it" for a long time.
Mr Brown, who is based at the university's Treborth Botanic Gardens said: "Over the last 10 years I was hopeful that it might bloom but it wasn't to be.
"This year's poor summer didn't augur well so you can imagine my shock when I arrived at work after the weekend to see it had sprouted a 1.6 metre (5ft) flower stalk with such force as to break the roof of the glasshouse."
In the days after it sprouted earlier this month, Mr Brown feared the force of breaking the glass may have damaged it, preventing further growth.
But, after "shaking itself off", the flower stalk continued shooting upwards, reaching a height of more than 6.2m (20ft).
Around 3,500 green and yellow flowers have now bloomed
"Side branches then revealed dense bunches of flowers which gradually opened to reveal approximately 3,500 bright lime green and yellow tubular blooms which have proved very popular with bees and wasps," he said.
The plant's official name is agave americana but it became known as the century plant in the mistaken belief that it takes 100 years to flower.
It is monocarpic which means this is the first and last time this shoot will flower.
In its native Mexican home, its flowers are pollinated by bats as well as insects and possibly birds, according to Mr Brown.
The sap, which fuels the plant's fast growth, is accessed by tapping the stem and is then fermented to produce tequila.
Its flowers can be cooked in tortillas while the leaves, which may remain fresh on the plant for up to 15 years, are an important source of fibre for communities of the Mexican desert.