The garden’s 1908 Edwardian glass- house will be closed until later this year for a total refurbishment which will improve both its appearance and environmental conditions inside.
Botanic garden team leader Alan Matchett said the work was needed due to gradual deterioration caused by the humid climate inside and the seasonal elements outside.
The last time the glasshouse went through a total refurbishment was in the early 1990s, Mr Matchett said.
"One glasshouse has already been emptied, leaving the tropical house and the cacti and succulent house still to be cleared," he said.
Most of the plants would be relocated to the garden’s propagation house in the upper garden until the refurbishment was completed.
Some of the larger succulents and palm plants would be a challenge to move but the garden’s staff would be extremely cautious with the relocations, he said.
Work would include replacing the glass, repairing window frames, doors and the outer metal structure, painting, drainage and mechanical upgrades of the louvre control to maintain desired heat and humidity inside.
Expected to cost about $591,000 the work was needed to maintain the historic building and ensure the garden retained its six-star status as one of New Zealand’s top gardens, Mr Matchett said.