The prosperity of Canterbury in the 1850s owed more to the export of merino wool and to the unexpected development of a market for the products of intensive agriculture on the Victorian goldfields than to colonising theories. Canterbury maintained something of an English class structure and a “landed gentry” because colonists with capital in the 1850s chose to invest it in sheep flocks on distant pastoral leaseholds rather than purchase the freeholds of arable farming estates near Christchurch. In the later 1850s and the 1860s it was the “small men”, including artisans and labourers, who were the purchasers of freehold land in Canterbury.

The “pastoral invasion” of the South Island grasslands had already begun when the Canterbury settlement was founded. Australian graziers with capital and merino sheep were arriving in the district and were occupying lands outside the Canterbury Block at low rentals. Godley and the Canterbury settlers, placing economic gain before theoretical principles, persuaded the Canterbury Association in 1852 to grant cheap pastoral licences on terms comparable to those of the New Zealand Government's Crown Lands Ordinance of 1851. Pastoral occupation surged rapidly across the plains. By 1855 all the plains and downland and the “front country” of the ranges had been taken up in runs of 5,000 to 10,000 acres. The tide paused for two seasons until C. G. Tripp and J. B. Acland proved at Mount Peel that sheep could be wintered successfully in the high country. Then the sheepmen moved rapidly into the alpine valleys and interior basins and by 1860 had established a skeleton occupation of all the grasslands back to the beech forests and snowfields.

Everywhere, stocking was preceded by vast tussock fires, and although necessary at first to clear spiny growth, massive burning became so ingrained in the habits of two generations of pastoralists that widespread and permanent damage to plant and soil cover has resulted. By 1858 Canterbury had surpassed Nelson as the premier sheep farming province, a position it lost to Otago, however, by 1867. Sheep numbers grew fivefold from 500,000 in 1858 to 2,500,000 in 1867 and to a peak of 5,000,000 in 1886. Thereafter Canterbury sheep numbers declined until the late 1920s. Although much attention has been given to the rapid spread of extensive pastoralism after 1852 and the manner in which it disrupted plans for close settlement, most of the population, in fact, continued to live near Christchurch. Of the 16,000 people in Canterbury in 1861, four-fifths lived in a narrow coastal strip between Rangiora, Christchurch, and Lyttelton and on small farms on the shores of the Banks Peninsula bays.

Mixed farming and closer settlement spread out from two points: from the early settled lands near Christchurch, and from Timaru, where the first direct immigrant ship arrived in 1859. Land sales were stimulated after 1856 when the price of rural land in Canterbury was reduced from £3 to 2 per acre and the minimum area from 50 to 20 acres. Near the towns this action helped the settler of limited means to become a landowner, but in more distant areas the large runholders were able to freehold the most desirable parts of their properties and check the spread of closer settlement.

Small farmers occupied the deep, fertile loams of the coastal lands, and with axe, spade, and wooden plough they cleared the flax and tussock, drained the swamps, and enclosed their fields with cob walls capped with gorse hedges. Heavy demands were made on Canterbury's meagre and patchy supplies of timber and many latter-day market towns, including Rangiora, Oxford, Geraldine, Temuka, and Waimate, originated as sawmilling centres in the 1850s and 1860s. Nor'west winds were a grave fire hazard and much of the Banks Peninsula forest and most of the timber patches on the plains and downland were accidentally destroyed before milling was complete.

In provincial New Zealand the strength of provincial sentiment diminished with increasing distance from the provincial capital. In the 1860s the growing community of South Canterbury, separated from the seat of Government in Christchurch by wide unbridged rivers and the sparsely occupied lands of mid-Canterbury, twice made a bid to become a separate province or county. In 1867 the General Assembly responded to Timaru's separatist agitation by creating the Timaru and Gladstone Board of Works – a body endowed with a specific proportion of the Canterbury provincial land revenues and authorised to construct and maintain harbour works and local roads and bridges.