For it to suddenly emerge in the gravel is rather astonishing and given the efforts we went to, pretty ironic Senior horticulturist, Jess Gould

Horticulturists have spent hours upon hours recreating the conditions needed to produce Grevillea maccutcheonii.

It is one of the most endangered plants in Australia and five years ago only 10 could be found anywhere in the wild.

Now one has sprung-up in a gravel bed in the garden's Great Glasshouse of its own accord.

One of these plants was grown using tissue culture at the King's Park botanic garden in Perth and sent to Wales in 1999.

Senior horticulturist at the garden in Wales, Jess Gould, said: "In previous years, we have managed to germinate and grow on some seed from the plant.

"But we went through the whole rigmarole of soaking it in smoke solution, and then putting the seed tray on a specialist hot bench which heats the soil in the day time and allows it to cool again at night - thus mimicking the conditions in the wild where plants germinate after fires in the ground."

Five years ago there were only 10 Grevillea maccutcheonii in the wild

She said their first success came in 2003 when visitors saw its red and yellow flowers for the first time.

They have continued to use the same painstaking method but now one has self-seeded and flowered unexpectedly.

"For it to suddenly emerge in the gravel at the side of the path is rather astonishing and, frankly, given the efforts we went to previously, pretty ironic.