For the past 20 to 30 years, the Agave americana plant growing on the corner of Erin St and City Rd may have been largely overlooked.
But since it sprouted an 8m-tall stem and started growing large yellow flowers, it has been hard to miss.
Dunedin City Council Botanic Garden collection curator Dylan Norfield said the plant only flowered once in its lifetime, usually between 10 to 30 years of age.
"Depending on conditions, and due to our cooler climate down here, it is likely to be closer to the older end of that age bracket.''
He said the plant was also known as a century plant.
"This has led many people to believe it only flowers once every 100 years.
"This is not the case, but it does refer to the fact that once it flowers, that plant will die.
"Luckily, Agave americana does have a habit of suckering [growing new roots] and the plant in question has several suckers at the base to take over when the adult plant flowers and dies.''
Mr Norfield said the plant was native to Mexico and the southern United States.
"Surprisingly, it does well in Dunedin. They like a position of full sun and good drainage, and the plant on Erin St has both of these.
"It is a great choice for the drought tolerant garden.''
He said even though the leaves of the plant only grew up to 2m long, the flower spike could reach 8m to 9m high, depending on how much energy the plant was able to store in its leaves and stem over its lifetime.
"The flowers are usually yellow, attracting tui and bellbirds, and as well as producing seeds, will often produce small plantlets on the stem which drop to the floor and can make roots.''
