Winemaker Nicholas Brown stands on the front steps of Black Estate winery, sweeping his arm around the line of the surrounding mountains which cup the Waipara Valley.
"Over here, there is glacial clay." Glaciers deposited this after they cut the valley. "So the hillside vineyards are on clay soil. There is limestone at the top of the hill and over time, the limestone has eroded and washed down into the clay." There are riverbed gravels with very little organic matter.
So, even in this one Waipara Valley, the land on which vines grow differs, following the sweep of Nicholas' arm.
And this landscape and this land, its aspect and climate, and the actual clays and gravels and chalks end up in the bottle.
The wines of the Waipara wine region, 54km north from Christchurch and a good day trip or lunchtime stop on the way to the thermal pools of Hanmer Springs, 74km further on, are distinctive and bespoke.
They are unique in the sense that, even within the Waipara Valley, there is variation, coming from the landscape and the 18 wineries and vineyards.
And in turning the vineyards back to organic methods, Nicholas is encouraging the vines' roots through two differing top layers of clay and into the chalk below - "getting the soil microbes going, to encourage the roots to explore the soil".
There is a lot of handwork in the clay limestone vineyards of Black Estate, which is near the town of Omihi.
From this, among others, Nicholas and wife Penelope Naish have a pinot noir that is soft and supple, a chardonnay from low-yielding fruit with intense flavours and a bright riesling.In their restaurant, which emphasises local fare, they are serving 2008 wines.
Nearby, among the cluster of other vineyards and restaurants in the Waipara Valley, is Pegasus Bay Winery, which is renowned as much for its food as its wine - and particularly for its long summer lunches.
"If you don't give it a couple of hours, you're not doing it justice," says local Scott Callaway, who's showing me round.
A family-run winery, it was established by medico and wine columnist Ivan Donaldson in 1986, and now involves his three sons, including winemaker Matt. Mr Donaldson developed a love of the history of wine as much as for the drinking of it.
In the tasting room, there's a fresh sauvignon semillon and the dry, lemony Bel Canto riesling. Riesling works well in this area. There's a chardonnay, a gewurztraminer and the Prima Donna pinot noir.
And cellar-door prices are good - for example, $26 for the sauvignon semillon, $30 for a bottle of riesling.
The restaurant and gardens are beautiful, and the welcome warm and enthusiastic.
After all, Waipara, says Nicholas Brown, "has a handful of passionate producers with high ambitions, and we are all motivating each other to raise the bars".
An excellent Waipara Valley map is widely available in the area, to guide visitors around the 18 wineries and vineyards, cafes and restaurants, accommodation and other attractions. waipara.co.nz.
Black Estate winery: blackestate.co.nz.
Pegasus Bay winery and restaurant: pegasusbay.com.
Hurunui tourism: visithurunui.co.nz.
Tourism New Zealand: newzealand.com.
Air New Zealand: airnewzealand.co.nz.
Stephen Scourfield was a guest of Tourism New Zealand.