Carpodetus serrata
A small tree up to 6 metres. It's branches spread out in flattened tiers which make for an interesting shape. The branches form a zig-zag with a leaf at each node. Well worth growing. This plant shows many of the features of NZ Plants: distinct juvenile and adult leaf shape and size, dioecious, Zig-zag or divaricate form.
The seeds are ripe when the berry is purple or black in May or June. If sown at this time of the year they should germinate by October. Quick growing seedling. Do not overwater while young.
If you wish to learn more about native plants I suggest one of these natural history books from fishpond