In contrast to the generally assumed transition from hunter-gatherer to agro-pastoralist, colonisers of South Island, New Zealand, central East Polynesians who practised shifting cultivation as a major component of their subsistence strategy, adopted a new economic strategy based on hunting of megafauna, giant flightless birds and marine mammals. This is in contrast to North Island, New Zealand, which is separated from South Island by only 20 km of ocean, and which was simultaneously colonised by settlers from central East Polynesia. In the northern half of North Island an economy based on horticulture was developed. The principal crop was an introduced tropical crop, sweet potato/k?mara (Ipomoea batatas), a frost-tender plant, that was converted from a perennial crop into an annual summer crop during a short growing season, with over-winter tuber storage in semi-subterranean storehouses and growth enhancing techniques. Other introduced tropical crops were grown in the northern part of North Island. Paper mulberry/aute (Broussonetia papyrifera) did not thrive and was little used in the late prehistoric period. Several native plants, with growth habits similar to Polynesian economic plants were semi-cultivated; the austral bracken fern (Pteridium esculentum) rhizome became an important food resource.

The two main islands of New Zealand, North Island and South Island, pass through almost 13 degrees of latitude. Thus the northern tip is in a subtropical climatic zone, while southwards New Zealand lies in a temperate climatic zone where mid-latitude westerlies prevail; frost can occur in any month, but in most parts there are few between December and March, and eastern South Island and the eastern southern half of North Island are subject to drought.

The colonisers successfully introduced five tropical cultigens in the north by developing new cultivation techniques, but in the south conditions were too harsh, thus they adopted a hunter-gatherer economy.