Trellising system
Trellising system refers to the structural framework used in viticulture to support, position and organise the permanent and annual growth of the grapevine. Together with pruning and training, trellising systems play a central role in controlling vine vigour, canopy structure, fruit exposure and mechanisation potential, directly influencing grape composition and wine quality.[1]
Definition and purpose
A trellising system consists of posts, wires and anchors designed to hold vine trunks, cordons, canes and shoots in a defined spatial arrangement. Its primary functions are to support vegetative growth, maintain canopy stability under crop load, and optimise the interception of sunlight while facilitating air circulation and vineyard operations.[2]
Trellising differs from the training system in that training defines the biological form of the vine, whereas trellising provides the physical structure that maintains that form over time.
Viticultural objectives
Effective trellising aims to achieve balanced vine growth by regulating shoot density, leaf area distribution and fruit positioning. Proper trellis design helps reduce disease pressure by improving canopy aeration, limits shading of fruit zones, and allows consistent ripening across the vineyard.[3]
In modern vineyards, trellising systems are also designed to accommodate mechanised pruning, harvesting and canopy management, improving labour efficiency and consistency.
Common trellising systems
A wide range of trellising systems are used worldwide, selected according to climate, soil, grape variety and production goals. Common examples include:
- Vertical Shoot Positioning (VSP), characterised by upright shoots trained between parallel foliage wires, widely used in cool to temperate climates.
- Geneva Double Curtain (GDC), which divides the canopy horizontally to manage high vigour sites.
- Lyre and other divided canopies, designed to increase light penetration in vigorous vineyards.
- Single-wire and low-wire systems, often associated with traditional or low-input viticulture.
Each system presents different trade-offs between vigour control, yield potential and wine style expression.[4]
Relationship to climate and site
Climate strongly influences trellis choice. In cooler regions, systems that maximise sunlight exposure are favoured, while in hot climates trellising may be designed to provide partial shading and protect fruit from excessive heat and sunburn.[5]
Site factors such as slope, wind exposure, soil fertility and water availability also determine trellis height, wire spacing and canopy division, linking trellising decisions closely to site selection.[6]
Impact on grape and wine quality
Trellising systems influence grape composition indirectly through their effects on microclimate and vine balance. Canopy architecture affects sugar accumulation, acid retention, phenolic development and aroma compound formation, making trellis design an important qualitative tool rather than a purely structural choice.[7]
As a result, trellising is often adjusted over time as vineyards mature or as production goals evolve.
See also
References
- ↑ Robinson (ed.), The Oxford Companion to Wine, Oxford University Press, 2015, ISBN 978-0198705383.
- ↑ Keller, The Science of Grapevines, 2nd ed., Academic Press, 2015, ISBN 978-0124199873.
- ↑ Smart & Robinson, Sunlight into Wine, Winetitles, 1991, ISBN 978-1875130033.
- ↑ Jackson, Wine Science, Academic Press, 2020, ISBN 978-0128161180.
- ↑ OIV, “Vine training and trellising systems”.
- ↑ Coombe & Dry, Viticulture Vol. 1, Winetitles, 1992, ISBN 978-1875130095.
- ↑ UC Davis, “Trellis design and vine balance”.