Zero days I will spend at backpackers or camping grounds and occasionally pamper my self with a motel room. For the rest of the time it will be in a tent or Hut. NZ has a great Hut system but you don't hit the first one until after Hamilton and it is not until the Tararua Ranges and South Island that they are frequent.
Normally when I go tramping I take Backcountry Cuisine Freeze Dry meals. They are simple to prepare, light and most of the meals taste good. I did find in my Stewart Island Tramp that by the 5th day the meals were not enough and I was always hungry. Also they are not cheap.