Terroir 2004 banner
IVES 9 IVES Conference Series 9 The South African vineyard landscapes: impact on long term cultural practices

The South African vineyard landscapes: impact on long term cultural practices

Abstract

This paper follows the one presented by Saayman at the International Symposium on Landscapes of Vines and Wines in the Loire Valley during July 2003. Where Saayman’s paper described the heritage and development of South African vineyard landscapes, this one focuses on how the landscape is used to assist in decision-making concerning the most important long term practices.
The diversity of South African vineyard landscapes, especially those in the Western Cape, prevents the application of recipes in vineyard practices. In this region, viticulture is practiced on coastal plains, undulating foothills and mountain slopes ranging from below 10m to above 500m altitude. These variations occur over short distances, frequently within one kilometer. A huge variation in soil type and exposure to sea breezes further increase the complexity of the landscape. Evidently the choice of rootstock and scion cultivar is critical and frequently situations are found where more than one rootstock and certainly more than one scion clone must be used in the same block.
Clearly, it is very difficult to create homogeneous vineyard blocks in this diverse landscape. Examples are presented of how to define vineyard block boundaries. Cool sea breezes during summer are responsible to prevent excess leaf and berry temperature increases. The choice of row direction is an important decision to utilize this beneficial wind effect, and where possible SW-NE row directions are used.
To create vineyard blocks on varying soil types is difficult. An important tool in this regard is to stadardise on the distance between rows and to vary the distance between vines in the row according to the vigour potential of the soil. Examples of this, as well as how the landscape affects the choice of the trellising system, are presented.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

E . Archer

Lusan Premium Wines, P O Box 104, Stellenbosch

Tags

IVES Conference Series | Terroir 2004

Citation

Related articles…

Main viticultural soils in Castilla – La Mancha (Spain)

Castilla-La Mancha is the biggest vineyard in the world. Once similar soils have been identified in Castilla-La Mancha (soil

Bacterial community in different wine appellations – biotic and abiotic interaction in grape berry and its impact on Botrytis cinerea development

An in-depth knowledge on the conditions that trigger Botrytis disease and the microbial community associated with the susceptibility/resistance to it could led to the anticipation and response to the Botrytis emergence and severity. Therefore, the present study pretends to establish links between biotic and abiotic factors and the presence/abundance of B. cinerea.

Analyse de la perception du terroir et de sa valorisation par les viticulteurs de l’Anjou

An integrated terroir characterization is currently realized in the French northern vineyard: “Anjou”. The concept of Basic Terroir Unit (B.T.U.) and its associated ground model “Rock, Alteration, Alterite” are used in this characterization. This work is coupled to a viticultural survey, based on parcels.

Photoselective shade films affect grapevine berry secondary metabolism and wine composition

Grapevine physiology and production are challenged by forecasted increases in temperature and water deficits. Within this scenario, photoselective overhead shade films are promising tools in warm viticulture areas to overcome climate change related factors. The aim of this study was to evaluate the vulnerability of ‘Cabernet Sauvignon’ grape berry to solar radiation overexposure and optimize shade film use for berry integrity. A randomized complete block design field study was conducted across two years (2020-2021) in Oakville, Napa Valley, CA, with four shade films (D1, D3, D4, D5) differing in the percent of radiation spectra transmitted and compared to an uncovered control (C0). Integrals for gas exchange parameters and mid-day stem water potential were unaffected by the shade films in 2020 and 2021. By harvest, berries from uncovered and shaded vines did not differ in their size or primary metabolism in either year. Despite precipitation exclusion during the dormant season in the shaded treatments, yield did not differ between them and the control in either season. In 2020, total skin anthocyanins (mg/g fresh mass) in the shaded treatments was greater than C0 during berry ripening and at harvest. Conversely, flavonol concentrations in 2020 were reduced in shaded vines compared to C0. The 2020 growing season highlighted the impact of heat degradation on flavonoids. Flavonoid concentrations in 2021 increased until harvest while flavonoid degradation was apparent from veraison to harvest in 2020 across shaded and control vines. Wine analyses highlighted the importance of light spectra to modify wine composition. Wine color intensity, tonality and anthocyanin values were enhanced in D4 whereas antioxidant properties were enhanced in C0 and D5 wines. Altogether, our results highlighted the need of new approaches in warm viticulture areas given the impact that composition of light has on berry and wine quality.

Cascading effects of spring weather conditions into grape berry ripening

The effects of climate change on viticulture are complex due to interactions among factors and cascading effects.