THE islands of New Zealand form a long thin exclamation mark in the vast gyre of the southern ocean relentlessly churning around the Antarctic continent. In the north, there are exuberantly colourful gardens of subtropical plants including New Zealand’s brilliant crimson-flowered Christmas tree – the pohutukawa. Further south is the very different palette of a true temperate climate. Plants wear their sensible seasonal livery under snow in winter, in the […]