Taro (Colocasia esculenta) was grown for its starchy tuber. It was considered a kai rangatira (food for important people). Early explorer William Colenso named 10 varieties from Northland, some of which were only eaten on particular occasions, and another nine from the East Coast and Hawke’s Bay. Like kūmara, these varieties were distinguished by size, sweetness and colour.
Taro needs plenty of moisture, and microfossil analysis of peat soils in Northland has shown that taro was grown in swamps with elaborate drainage networks to maintain appropriate conditions. These sites, which are similar to the Polynesian wetland ditch-and-irrigation systems, were no longer in use by the late 18th century. Only dry-land taro gardens were reported by early European observers, who saw taro being grown in hollows or on flattened areas.
Very little is known about uwhi (yam, Dioscorea species) cultivation in New Zealand. A growing period of eight months or more is needed for the tubers to reach maturity (compared to five months for kūmara). As a result, yams could not be grown in many areas, and yields may have been low. Eighteenth-century European visitors saw yams growing in gardens in Northland, and in Tolaga and Anaura bays on the East Coast. The plants have a twining habit and, like kūmara, were planted on puke (mounds). However, introduced vegetables – especially potatoes – later replaced yams.
There are different traditions about the arrival of cultivated plants in New Zealand. The Horouta canoe is said to have brought the kūmara, taro, hue and uwhi. Ngāti Whātua believe that Kui, a wife of the ancestor Tumutumuwhenua, introduced taro and hue. In another tradition, the Tainui waka arrived carrying hue, aute and kūmara.
Tī pore (Pacific cabbage tree, Cordyline fruticosa) was grown primarily for its tap root, which, after bruising and steaming in a hāngī (earth oven), was sweet and edible. The central shoot and stem pith could also be eaten. Tī pore is now extinct in the wild in New Zealand, but grows well on Raoul Island in the Kermadecs, where it may have been introduced during Polynesian voyages south to New Zealand. The shrub-like plant was reproduced vegetatively, but took several years to reach maturity. It seems to have been grown only in the Far North of New Zealand. Polynesian settlers assigned the name tī to the native New Zealand cabbage trees, also a Cordyline. They cooked the root in a similar way, but did not cultivate the plants.