One vine, two parts: the graft doing its job without appearing on the label

29 October 2026 · sommelier.vi.cat

Curiosities · Vine or variety · 29 October 2026 · sommelier.vi.cat

A label says Xarel·lo, Syrah or Chardonnay, and the botanical story appears to be settled. Yet many of these vines lead a shared life: one part provides the variety we recognise, while another supplies the roots. This is neither a winery secret nor a clandestine blend. It is a graft. And the part that rarely makes the photograph has plenty to do.

Who does what?

In a grafted vine, the rootstock supplies the rooted portion; the scion supplies the variety grown for its grapes. Their union allows them to grow as a functioning plant. If the upper part is Syrah, its bunches remain Syrah: the roots do not add another grape variety to the tank. Oklahoma State University’s February 2017 guide explains this distinction and contrasts it with an own-rooted vine, which grows on its own roots.

Three ideas should be kept separate. Grafting joins plant parts. Crossing varieties through sexual reproduction is another operation. Blending wines or grapes during winemaking is a third. Sharing the language of combination does not make them the same thing. The family tree, the nursery and the blending bench do not work in the same department.

Phylloxera explains much of the history

The use of resistant roots responds, crucially, to the damage phylloxera can cause to the roots of the European grapevine. Rootstocks allow valued varieties to be maintained on a root system suited to facing that threat. Penn State Extension’s grape-growing documentation helps distinguish protection of the roots through plant material from assuming that the entire plant is protected against every problem.

That second idea would be an exaggeration. A graft is not a shield against every disease, drought or poor growing decision. Nor should any form of resistance be described as universal immunity. In viticulture, “resistant to what?” is a considerably more useful question than simply “resistant”.

Roots are not a neutral stand

Choosing a rootstock requires attention to soil, available water, pest risks and its combination with the grape variety. Penn State’s wine-grape production guidance places the choice within vineyard planning. A recommendation intended for one site should not automatically become a recipe for another.

For reading a wine profile, there is a straightforward lesson: knowing the variety does not mean knowing every planting decision. The root system contributes to how the whole plant functions, but does not entitle us to infer a tasting note on its own. There is no reliable shortcut from a rootstock name to “expect pear and a three-minute finish”. That would be convenient. It would also save far too many questions.

The nursery is part of the wine story too

Before a plant reaches its plot, someone has had to prepare and check that union. The Institut Français de la Vigne et du Vin explains nursery production, in which the identity and health of plant material are part of the work. Precision matters from the beginning: holding two pieces of plant together is not enough.

This broadens our understanding of origin. We quite rightly ask about villages, plots and vintages. Asking how a vineyard was established reveals another layer of decisions. Nobody needs to recite rootstock codes to enjoy a glass. Recognising that viticulture also happens below ground is enough to begin with.

A detail that prevents confusion

If a grafted plant loses its upper portion and regrows from the rootstock, that growth does not necessarily represent the variety originally intended for cultivation. The distinction appears in the Oklahoma guide linked above. It is a useful example of why “the vine is sprouting again” is not the whole story. Where the shoot originates matters.

Similarly, “own-rooted” in a wine description should not automatically be translated as “better wine”. It describes a condition of the plant. The quality of a bottle requires many more explanations. Turning an agronomic fact into an instant medal leaves out the site, harvest, vineyard management and winemaking.

Bringing the curiosity back to the glass

The next time you explore our wines or a Territory article, you can add a question to your repertoire: is there documented information about the plant material in this particular vineyard? If there is not, we leave the gap open. This article does not assign a particular rootstock to any of Vikipedia’s bottles.

The grape variety deserves its prominence. The roots also deserve to be remembered. One name appears on the label; the teamwork usually stays underground.

Sources and method. Oklahoma State University, Becky Carroll, HLA-6253, February 2017; Penn State Extension growing and production resources; IFV nursery-production guidance. Consulted on 29 October 2026, with links in the text. Comparisons and questions are editorial explanation, not tasting descriptions.