Recent research at our Snake's Tongue vineyard block has revealed the vines, planted in 2007, are grafted to Riparia Gloire – a highly regarded prestige rootstock found in many of the great French vineyards. It is not often used in organic vineyards in New Zealand due to its susceptibility to drought conditions, however with our regenerative viticulture programme, we found a way for it to thrive. Combined with Abel clone, it produces our most exceptional Central Otago Pinot Noir from Low Burn, the Pyramid Valley Snake’s Tongue Pinot Noir.
We recently conducted research with Riversun Nursery to identify the rootstock in our Snake's Tongue block and found that the vines planted in 2007 are grafted to Riparia Gloire – a rootstock at times considered problematic for organic growers.
Riparia Gloire is traditionally considered a low vigour rootstock with a shallow rooting architecture. Discovering this is what we have in the Snake's Tongue block was surprising given we've managed to dry farm that block for half of a season – through the hottest part of summer without using irrigation.
This finding challenges fundamental assumptions about rootstock performance. Riparia Gloire has historically been avoided by organic growers because its shallow root structure was believed to require constant irrigation to prevent water stress. Yet our Snake's Tongue block has not only survived extended dry periods but has consistently produced exceptional quality fruit.
Vine husbandry over genetics
The key to understanding this apparent contradiction lies in how we manage the vineyard. My hypothesis centres on our subsurface mid-row irrigation combined with regenerative organic practices. We've created a greater volume of soil that the vines can explore, and along with our regenerative organic practices – using cover crops, increasing organic matter – we're able to hold more moisture in the soil. At the same time, our subsurface irrigation system delivers water directly to the root zone and encourages the vines to explore the whole area.
It's made me realise that the way we manage the vineyard may have more of an impact than what we plant. The conversations about more drought-tolerant rootstocks may be less relevant than how we manage those vines.
This was also evident from research presented at the recent Organic Winegrowers conference, where rootstock trials on supposedly drought-tolerant varieties showed that irrigation practices negated any hereditary deep-rooting traits. When water is readily available at the surface, vines simply follow the water rather than developing the deeper root systems they're genetically programmed for.
A different approach
There's plenty of people who've got Riparia Gloire planted across Central Otago. Those farming organically have tended to avoid it because it's so devigorating and with the extra competition under vine, people are running into trouble. But in our system, having mid-row subsurface irrigation below the surface plants and in the vine root zone, the vines are seemingly able to compete and have access to that water.
Overall, we’re still using a lot less water due to holding a lot more water in the soil with the increased organic matter. I believe our success with this rootstock is twofold – more organic matter in the soil holds more moisture, and we're applying water below ground in the root zone in the middle of the row, encouraging the vines to explore the whole area of land rather than just the strip thirty centimetres wide under the vines.
What's next?
Much of our current understanding is based on above-ground observations and assumptions about what's happening below the soil surface.
The next step would be to measure actual root volume and architecture, though current technology limits non-destructive analysis. In future we might see 3D lidar technology that could figure out the volume of roots these vines have, without digging them up.
For now, we've got data from vine stem water potential measurements showing the vines don't need additional water. We're not, not irrigating because we don't want to – we've got data to show that the vines are thriving without it.
It’s my view that we need to look at this holistically across the season. It's not just about how much water we apply when frost fighting – it's about the entire management approach and how all these practices can work together.
The Snake's Tongue block continues to provide compelling evidence that vineyard management can overcome supposed rootstock limitations. Sometimes the most valuable discoveries come from questioning what everyone "knows" to be true.
Nick Paulin
National Viticulturist (the Vine Gardener)
Pyramid Valley, Smith & Sheth, Lowburn Ferry
Aotearoa New Zealand Fine Wine Estates
October 2025 celebrates the launch of the third vintage of the Pyramid Valley Snake’s Tongue Pinot Noir, from the stunning 2023 Central Otago vintage. For a story of the wine and current availability click here.