There are three species of Wisteria grown commonly in New Zealand. W. sinensis flower on bare stems, W. brachybotrys tends to flower with the first leaves and W. floribunda forms which tend to flower with the first flush of foliage but they have longer racemes which make them better candidates for pergolas and other growing frames.
All forms are suitable to train as standards.
Wisterias prefer a soil rich in organic matter to hold adequate moisture through the summer months, since moisture availability is important for flower initiation. A little lime is also beneficial, as it is to all legumes. Once the plants are established, too much water and fertiliser can encourage excessive growth at the expense of flower production. The red pigmentation in most varieties appears to be enhaced by warm temperatures at flowering time. This is particularly so with 'Royal Purple' and 'Amethyst'.