Murray Gribben is the new chief executive of the Government's Crown Irrigation company, which has $400 million to spend on irrigation projects nationwide.
Mr Gribben has worked extensively in the investment sector and will start on 18 November.
In a statement, Mr Gribben said he was excited at the chance to transform the productivity of the country's farmland.
He said he had owned and managed a South Wairarapa farming business, and that had given him first-hand experience of how pivotal water was to agriculture.
Crown Irrigation will provide funding to get investment-ready irrigation schemes up and running, getting its money out after farmers buy in.