I am going to look for some answers.
Until 1839 there were only about 2,000 immigrants in New Zealand; by 1852 there were about 28,000. The decisive moment for this remarkable change was 1840. In that year the Treaty of Waitangi was signed. This established British authority in European eyes, and gave British immigrants legal rights as citizens. The treaty helped ensure that for the next century and beyond, most immigrants to New Zealand would come from the United Kingdom.
While many of the early English immigrants came from the south, later in the 19th century they came from the industrial areas in the north, from Yorkshire and Lancashire, and they brought new traditions.
Investors in the The New Zealand Company were promised 100 acres (40.5 hectares) of farmland and one town acre; the initial 1,000 orders were snapped up in a month. But how to attract the labourers? To combat negative notions about New Zealand, the company used books, pamphlets and broadsheets to promote the country as ‘a Britain of the South’, a fertile land with a benign climate, free of starvation, class war and teeming cities. Agents spread the good news around the rural areas of southern England and Scotland. As added inducement the company offered free passages to ‘mechanics, gardeners and agricultural labourers’. Some responded and the first ships arrived in Wellington from January 1840,
By 1843 the new settlers were short of food and the company was virtually bankrupt. Two interventions by the British government saved it from total disaster. Yet the company began to organise large-scale migration to New Zealand. Advertising and propaganda attracted thousands of people over the next 100 years, and the main drawcard, the free or assisted passage, became hugely important. Company immigrants sent letters back home which encouraged others to come out .