A giant of the garden

I've heard it suggested that the best time to plant a tree was 20 years ago and that the next best time is today.

Trees provide a garden and landscape with definition and a framework. From this beginning structure you can hang all the tinsel and decorations you know and want - completing your vision with flowering shrubs and herbaceous drifts.

The Dunedin Botanic Garden lower garden car park was developed and planted in 1993 on a clear site. Before anything else, the largest growing and long-lived specimen trees were placed and planted.

Twenty years later, standing impressively high already is one beautiful blue-foliaged coast redwood, Sequoia sempervirens ''Filoli''. The coast redwood is one of the fastest and tallest-growing trees in the world and this blue-leaved cultivar grows at about half the rate of the species - still really fast.

Sequoia sempervirens often reaches up to 100m high, with one recorded at 112m. They are also very long-lived, the average age being 500 to 700 years. It's an impressive narrow conical shape, with elegant draping branches.

This tree is too big for our average city gardens, so having the botanic garden space in our central city to marvel at these living skyscrapers is the next best thing to viewing them on the coastal slopes of California and southern Oregon where they originate.

- Marianne Groothuis is the camellia and themes collection curator at Dunedin Botanic Garden.