Mather said the impact of traditional farming had damaged the thin layer of topsoil sitting on a solid pan.
"It was in poor condition from plugging, and rainwater would run straight off."
With his dream of a permaculture paradise, he set about making big changes to two of the 10-acre blocks to prepare them for tree crops. The third block is being used to farm alpacas.
Mather said he had taken the concept of humping and hollowing of the land a bit further, in a more sophisticated layout for drought resistance.
"I used a laser level to find the contours to follow so that the ditches capture the rainwater and it seeps into the soil. I had to dig right into the clay.''
Ditches and mounds have been made in various heights and depths, depending on the situation.
Mather said some people using the technique preferred shallow humps and hollows so they could still drive over them, but in his case, he needed deeper ditches because of the pan.
Ring ditches encircle the top of hillocks and others lower down the contours have been strung together to make long channels to spread the water as far as possible.
Mather chucks in grass cuttings, old cardboard and tree bits to help keep the waterways cool, and to brew up a soil-improving stew.
"The green waste helps to shelter the water, limiting evaporation and allowing it to soak into the ground really slowly in a plume.
"The trees then draw this water up for their feeder roots,'' he said.
Mather has created a subtropical microclimate on the property, despite being on a ridge.
There are thousands of trees – he has lost count.
"This year I have planted 600 trees and last year was 1200. I would estimate there are about 5000 trees planted now. There is still room for another 5000,'' he said.
Trees are mixed in and chosen for a whole range of uses, including fruit and nuts, shelter, timber and animal fodder.
He likes to try to grow the unusual, just to prove he can.
"The trees are all mixed in together, as would occur in a forest. I plant them in groups together so they can help each other out.
"If there is a problem that develops on one type of tree, it is less likely to spread to all the others of its type because they are grown separately in groups with other types of trees.''
Pine nuts, tropical apricots, many types of acacias, blackwood, sugar cane, bananas, apples, figs, peaches and plums are dotted all around.
Tagasaste or tree lucerne is mixed in for quick shelter.
"It is fantastic because it grows to about 4m very quickly.''
Mather is against a monoculture.
"If you just grow one species you are going to have problems with bugs or disease.''
Another big difference in Mather's property is the proliferation of kikuyu. Pathways are mown, but otherwise it is allowed to grow. In many places it is at least knee high.
"I stamp it down around the smaller trees, but I don't pull it out or mow it. It is all part of keeping the soil protected and the moisture contained,'' Mather said.
"Once the trees are big enough to create shade, the kikuyu grass is no longer a problem.''
With no sprays being used on the property, there is a resounding chorus of golden bell frogs from the waterway edges.
Other residents include ducks, turkeys, 20 alpacas, a lone gander that protects the ducks, guinea fowl and hens.
"Guinea fowls make a huge amount of noise, but they are good at pest control,'' he said.
With a veritable pantry growing on the property, the couple sell produce at markets in Kerikeri, including bananas, two types of passionfruit and papaya.
