Practical handbook of grapevine pruning

Franco France 42,00 € Franco tous pays 56,00 €
OU
Auteur(s) André Crespy
Nb pages 160
Année d'édition Non
Langue(s) Anglais
Autres versions disponibles Français, Espagnol
Récompenses Non

160

Introduction

Why Prune?

Over the centuries, careful observations have enabled wine growers to determine the most suitable vineyard practices for each wine region in order to get a satisfactory crop each year. These practices include vine spacing and cluster height in order to obtain a sufficient quantity of grapes of good ripeness. We should not forget that early growers in France were constantly in search of proper ripeness and that their efforts in this area formed the backbone of the current appellation system (Appellation d’Origine Contrôlée or AOC). In recent years, climate change is erasing the memory of this once overriding problem, which was remedied in the winery by chaptalization, or sugar addition. In the last decade, good to exceptional vintages have followed one after the other in France, much to the chagrin of beet sugar growers. Grapes are harvested earlier, and tartaric acid is replacing calcium carbonate as the additive of choice, now that acid deficiency is supplanting excess acid as the most common problem. However, in other respects, nothing has changed at all, and traditional vineyard practices continue to be used.

One of the best illustrations of the negative effects that occur when traditional practices continue unabated in the face of climate change can be found with Grenache in the Côtes de Rhône, Costières de Nîmes and Coteaux du Languedoc appellations. In these vineyards, Grenache now ripens extremely quickly, but with such little colour that it is hard to compensate through blending with other varieties.

The definition of suitable vine spacing and crop yield (tonnes/ha) depends on two factors in the vineyard:
• Each vine is assigned a volume of soil to occupy, and it must remain within this volume, year after year.
• Each vine must supply a certain quantity of grapes, as determined by the number of fruitful buds left on the vine.

In general, winter, or dormant, pruning is what determines these two factors, while summer, or green, pruning is used to correct any imbalances (through disbudding, crop thinning, etc.).

Contents

  • Introduction
    • - Why Prune?
  • 1 - General Principles of Grapevine Pruning and Physiology
    • 1.1 - The Vegetative Cycle in Temperate Climates, or the Four Seasons of the Vine
      • Spring
      • Summer
      • Autumn
      • Winter
    • 1.2 - Sap Flow (Xylem Sap and Phloem Sap) during the Vegetative Period
    • 1.3 - The Shoot and Its Organs (Leaves, Clusters, Tendrils, Internodes and Buds)
      • Bud Fertility
    • 1.4 - Vine Vigour and Its Measurement: Pruning/Vigour Adjustments
      • Changes in Vigour
    • 1.5 - Pruning Grapevine Organs (Canes, Spurs, Cordons and Two-Year-Old Wood) and Its Consequences – Counting Fertile Buds
  • 2 - General Principles of Grapevine Pruning and Training
    • 2.1 - Vineyard Preparation
    • 2.2 - Adaptation to Soil and Climate Considerations
      • Water Stress
      • Heat Stress
      • Spring Frost
      • Wind and Relative Humidity
    • 2.3 - Adaptation to Quality Considerations
      • Effective Leaf Area and Crop Yield
      • Search for Ripeness, Balance, Colour and Aromas
  • 3 - Training Systems and Grapevine Formation
    • 3.1 - Planting – Preparation of Young Vines
    • 3.2 - Modern or “Fan-Type” Head/Goblet Training
    • 3.3 - Royat Cordon Training (One or Two Arms and Alternating)
    • 3.4 - Guyot Cane Pruning (Simple, Double, Enhanced and Short)
    • 3.5 - Other Systems
  • 4 - Pruning and Disease
    • Protection of Pruning Wounds
  • 5 - Pruning and Budbreak
    • Apical Control
    • Spring Frosts and Budbreak
    • How Frost Affects the Grapevine
  • 6 - Pruning Equipment and Organization
    • 6.1 - Pre-Pruning Equipment
    • 6.2 - Pruning Equipment
    • 6.3 - Disposal and Re-Use of Pruning Wood
  • Appendices