Attending Christchurch Boys' High School, Hartland was marked out as a talent early on, and aged 19 he was picked for the New Zealand Young Cricketers, who toured Australia in 1985–86.
He also played two seasons of second XI cricket for Northamptonshire in 1987 and 1988, and in 1988–89 Hartland hit his maiden first class century, in his fourteenth match.
England were put in to bat, made 580 for nine declared, before spin bowler Phil Tufnell took eleven wickets in the match, including Hartland twice, for 22 in the first innings and then 45 in the second when stumps were drawn on day four.
Hartland had still not passed fifty in six Test innings, but was still taken on tours of Zimbabwe and Sri Lanka in 1992–93, and though he did not play a Test against Zimbabwe (with Mark Greatbatch and Rod Latham preferred as openers), he played his first ODI on that tour, scoring five runs from number three in the batting order as New Zealand won by four wickets.
Greatbatch and Latham were dropped for Sri Lanka, however, and Hartland was back as opener together with Wright; after he was out to Dulip Liyanage for 3 in the first innings, and Sri Lanka had declared 39 runs ahead with five sessions remaining, Hartland batted for four hours in an opening stand worth 110 with Wright, making his maiden Test fifty.