Final Report: This is a completed project for the Washington Grape & Wine Research Program

Title: Influence of cultivar, environment and management on grape yield components and quality (Objective 1: Optimize irrigation strategies for high-quality white wine grape production)

Project Duration: 2014-2017

Primary Investigator(s): Markus Keller
Organization: Washington State University
Address: IAREC, 24106 N. Bunn Road, Prosser, WA 99350

Cooperator(s): James F. Harbertson
Organization: WSU Tri-Cities
Description of participation: Fruit analysis, wine making and evaluation

Cooperator(s): Russell Smithyman
Organization: Ste. Michelle Wine Estates
Description of participation: Field trial oversight and vineyard management

Project Summary:

The Washington wine industry is continuing its rapid expansion phase, yet many wine critics complain that the overall quality of white wines from this state lags behind red wine quality. Two white varieties, Chardonnay and Riesling, account for 75% of all white wine made in Washington, and will continue to be a major component of the industry’s expansion. Due to the arid climate in eastern Washington, drip irrigation is the principal management tool to impact yield, quality, and sustainability of premium grape production. However, virtually no research has been conducted to determine optimum irrigation strategies for white varieties. This project used Chardonnay and Riesling to compare three tools to aid irrigation decision making, and to study the impacts of irrigation regimes on grapevine growth, physiology, and fruit composition. The goal of this project was to provide basic information to develop practical recommendations for irrigation decision-aid tools and irrigation strategies to enhance white wine grape production. The project places valuable information in the hands of grape growers, enabling them to make better, science-based decisions regarding application and conservation of limited irrigation water. It also lays the foundation for the development of more effective irrigation strategies for the wine industry, which will permit improvements in fruit and wine quality through the judicious application of deficit irrigation strategies with a focus on white wine grapes.

Read more by downloading the full report above.

Irrigation // Viticulture //