Much work needed to mimic alpine habitat

New Zealand has a distinctive alpine flora. About 93% of the species that grow above the treeline occur nowhere else in the world.

Alpine plants are a horticultural specialty: to grow these plants requires more attention and care than your average garden plant. In the wild, they look perfectly delightful in howling winds, blazing sun, or freezing cold. At low altitudes, alpine plants can be absolute divas when it comes to their growing conditions. Most demand excellent air flow and good light levels. They also need ample water but perfect drainage.

During the last few weeks, an exciting new extension has been taking shape to the alpine scree in the upper garden. A miniature mountain ridge has been built from rocks and soil to add some height and drama to the scree garden and nearby garden beds have been extended and linked via a new pathway.

Drainage was a key consideration in the construction of the new mini mountain. Large rocks and a gritty soil mix will keep plants’ crowns well above the clay loam base. Deep pockets and vertical fissures will provide cool, loose root runs. The rocks will help to cool and moisten the soil and provide some protection from fierce summer sun.

Aside from paying homage to the wild environments of the southern highlands, this development has established the conditions necessary to grow some of New Zealand’s choice alpine plants, in particular alpine plants, grasses and shrubs of Otago and the wider South Island region.

Garden Life is produced by the Dunedin Botanic Garden. For further information contact Kate Caldwell.