Clone

A clone in winemaking refers to a genetic variation of a grape variety that has been propagated asexually (through cuttings rather than seeds) to preserve its specific characteristics that are created by taking vine cuttings from a mother vine, ensuring that the new vines are genetically identical to the original. The propagation process involves using vine cuttings to maintain genetic consistency across plantings. In viticulture, it is considered a type of cultivar, and the term ‘cultivar’ is often used to describe specific wine grape selections chosen for their unique traits.

Over centuries, grapevines undergo slight natural mutations, creating subtle variations within the same variety. Grape varieties such as Pinot Noir, Pinot Gris, and other wine grape varieties may have multiple clones. There are dozens of different Pinot Noir clones, each with slightly different characteristics in berry size, cluster structure, ripening time, flavor profile, or disease resistance yet all are still technically Pinot Noir. New vines are often propagated by taking cuttings from these selected clones to maintain their desirable qualities.

Usage of Clones In Winemaking

Clones are used by winemakers and vineyard managers to achieve specific goals. The winemaker plays a crucial role in choosing wine clones to achieve their desired wine style. Winegrowers carefully select specific vines and wine clones to optimize vineyard performance and wine quality.

Blending for complexity: Many premium wineries plant multiple clones of the same variety in their vineyards. Different clones ripen at slightly different times and contribute distinct aromatic and flavor profiles, which can be blended to create more complex, layered wines. Blending grapes from individual clones or producing single clone wines can showcase unique characteristics. Using other clones alongside the main clone can further enhance the complexity of many wines.

Matching terroir: Certain clones perform better in specific climates or soil types. A clone that thrives in cool climates might struggle in warmer regions, so growers select clones suited to their particular site conditions. Nurseries provide guidance and supply the best clones and rootstock combinations for specific regions, helping ensure optimal vineyard performance.

Quality enhancement: They can be selected for desirable traits like smaller berries (which have a higher skin-to-juice ratio, yielding more concentrated wines), looser clusters (which reduce disease pressure), or specific flavor characteristics like spiciness, fruitiness, or structural tannins. Sourcing certified clones from reputable nurseries is important to ensure vine health and quality.

Viticultural management: Some clones are chosen for practical reasons such as consistent yields, disease resistance, or predictable ripening patterns that align with harvest schedules. Selecting certain clones can improve consistency in yield and wine style. The choice of rootstock, often provided by nurseries, also plays a key role in vine health, disease resistance, and adaptability.

Why is it important

Clonal selection has become increasingly important in modern viticulture for several reasons. Around the world, winegrowers practice clonal selection and often share their knowledge and experiences with each other, sometimes over dinner, to improve vineyard outcomes and wine quality.

Quality control: By selecting proven clones with desirable characteristics, growers can more predictably achieve the wine style they’re aiming for, reducing variability and risk.

Adaptation to climate change: As growing conditions shift, having access to clones with different ripening times or heat tolerance gives growers flexibility to adapt their vineyards. Different regions, such as California and Willamette Valley, require clones specifically adapted to their unique climates, and the choice of which cultivars and varietals are planted can be critical for success in these areas and other regions.

Preservation of heritage: Clonal selection helps preserve ancient vine genetics. Some clones trace back hundreds of years and represent important genetic diversity that might otherwise be lost. The historical significance of Burgundy and France in the development of Pinot Noir clones is profound, with French viticulture and institutions like UC Davis playing a major role in the spread of clonal material to other regions around the world.

This tradition extends beyond Pinot Noir to other important varietals such as Chardonnay, Cabernet Sauvignon, Cabernet Franc, Syrah, and Sauvignon Blanc, all of which have notable clonal selections that contribute to the heritage and diversity of vineyards globally.

Economic viability: The right clones can improve vineyard health, reduce crop losses from disease, and produce more consistent quality, all of which impact a winery’s bottom line. Nurseries in different regions provide certified clones and cultivars suited to local conditions, supporting growers in making economically sound planting decisions.

Terroir expression: Paradoxically, while clones are about control, selecting the right clones for a site can actually enhance the expression of terroir by ensuring the vines are well-suited to their environment and can fully reflect the characteristics of their location. The choice of varietals and cultivars planted in a vineyard directly influences how terroir is expressed in the resulting wine style.

When is a clone not used

There are several situations where specific clonal selection is not employed:

Mass selection: Some traditional wineries prefer “sélection massale” (mass selection, also known as massal selection), where cuttings are taken from multiple vines in the vineyard that show desirable traits, rather than from a single mother vine. This maintains genetic diversity rather than genetic uniformity.

Field blends: In some traditional wine regions, vineyards historically contained mixed plantings of different varieties and naturally occurring variations, all harvested and fermented together. Some producers maintain this practice rather than planting specific clones. Field selections involve choosing specific, desirable vines from wild or established vineyards for propagation, often capturing natural mutations and enhancing regional character.

New plantings in developing regions: In emerging wine regions or when planting less common varieties, specific clones may not be available or catalogued, so growers plant whatever material they can source.

Seedling vines: Though rare in commercial viticulture, some experimental vineyards grow vines from seed rather than cuttings. Each seedling is genetically unique and technically not a clone. Wild grapevines contribute to genetic diversity, as their natural mutations and adaptations can introduce unique traits into new plantings.

Economic constraints: Small-scale or resource-limited growers may not have access to specialized clonal material and instead use whatever certified vine stock is locally available and affordable. Nurseries are a key source of vine material, but access to specialized nurseries may be limited in some regions.

Conclusion

Clonal selection represents a sophisticated tool in the modern winemaker’s arsenal, allowing for unprecedented control over vine performance and wine character. It bridges traditional viticulture with scientific precision, enabling growers to both preserve centuries-old genetic heritage and adapt to contemporary challenges like climate change and evolving market preferences.

However, the art of winemaking still requires balancing this precision with other factors—site selection, vineyard management, and winemaking technique all remain crucial. The most successful producers understand that clones are one piece of a larger puzzle, using them thoughtfully to enhance rather than override the natural expression of their vineyards. As our understanding of vine genetics deepens, clonal selection will likely become even more refined, offering exciting possibilities for the future of wine quality and diversity.