The early Hawaiians were primarily fishermen and cultivators. On their colonizing trips from their homeland they brought in their canoes planting stocks of their primary staple food crops as well as of plants yielding materials for housing, clothing, and utensils and of ornamental and medicinal value. Establishing and nurturing these plants in the fertile and well-watered soil of their new home, they eventually formed the basis of a well-developed agricultural economy.
A few edible food plants were indigenous to the Hawaiian Islands. Those used and carefully tended were pandanus and some ferns and probably 'ohelo and 'akala. The main native farming implement consisted of the o'o, a digging stick of hard wood of variable length, from six to nine feet long, with either a flat point or a flat blade. With the additional use of adzes, fire, and cutting implements, the early Hawaiians were able to clear vegetation; control streams by constructing dams, irrigation ditches, canals, and terraces; cultivate the soil of mountain slopes and valley bottoms; and build stone walls to arrest erosion.
Sometime during the settlement period, probably after crops were growing well and domesticated animals were reproducing, an economic shift from the sea to the land took place. As the population grew, this would have provided a more efficient means of subsistence than total reliance on fishing. Some farming was done in open grassland and forests, where irrigation was not necessary because of sufficient rainfall. Other crops grew in the lowlands or alluvial valley bottoms, where flowing water provided irrigation.
The most widely cultivated food plant of the early Hawaiians was the taro, whose tubers were baked, pounded, and mixed with water to make poi, staff of life of the Hawaiian culture, Wet taro, requiring abundant fresh water, was planted in pond fields near springs and freshwater marshes and on the flood plains of perennial streams, arranged in terraces so that diverted water could flow from the higher to the lower patches. Canals, constructed of earth and stone embankments, channeled water from streams or springs to irrigate these fields. Dry or non-irrigated taro required less water and was cultivated in upland grasslands, rain-soaked forest areas, and under mulch.
Several other dry land crops were also important food items. They were cultivated by means of swiddening — clearing vegetation by cutting and burning, followed by alternate periods of planting and leaving the land fallow. Sweet potatoes comprised the main crop where insufficient water occurred to grow taro. Breadfruit trees were planted in groves in sheltered areas with fertile soil and little wind. Numerous varieties of bananas grew in clumps around taro patches and in gulches. Yams were raised to some extent in the early days, but because of their mealy texture were not a favorite food. Later they were grown to sell to sea captains because they spoiled less quickly than taro or sweet potatoes. Other vegetables in the Hawaiian diet included coconuts, sugarcane, arrowroot, and seaweeds. Other plants extensively cultivated were the paper mulberry for manufacturing barkcloth (kapa), the 'awa for use as a narcotic, bottle gourds used for containers and musical instruments, screwpine (pandanus) used in making mats, and a variety of other useful plants.
As with all other aspects of Hawaiian culture, agricultural practices closely interfaced with religion, traditions, and customs. Because this endeavor was so dependent on the powers of nature, every step of the agricultural cycle — preparing the land, planting crops, caring for plants, and harvesting — was accompanied by appropriate ceremonies.