The Blue Mountains Rhododendron Society celebrated its 50th birthday on Saturday, with cake and champagne in the Lodge at the Rhodo Gardens in Blackheath.
It was April 1969 when a group of local nurserymen gathered to find a way to celebrate the rhododendrons of the Upper Mountains.
They eventually got the use of 18.5 hectares of Crown land in Blackheath and, within a year, the Campbell Rhododendron Gardens was established. It was named after two of the driving forces behind the gardens, Norm and Olive Campbell.
A team of volunteers planted hundreds of exotics - rhododendrons, azaleas, camellias, viburnums, flowering cherries, maples and other deciduous trees - under the native bush canopy.
At Saturday's party, the society's third president, Ivan Menzies, was given life membership of the society by the 20th - and current - president, Alan Lush.
And a book featuring photos of the gardens taken by David Cook and Jimmy Lim was launched.
The actual gardens will turn 50 next year.