Withholding water from this Columbia Valley Merlot vineyard desiccated the basal leaves by mid-July, eliminating the need for leaf removal. Using deficit irrigation in Washington State on wine grapes, particularly red varieties, has many benefits—smaller berries, better fruit exposure, and more open canopies for spray penetration and air circulation. But the biggest advantage is cost. “The main reason we should be practicing deficit irrigation is a savings in costs,” said Dr. Russell Smithyman, director of viticulture for Ste. Michelle Wine Estates. Hand leafing, at $70 to $100 per acre, and mechanical leafing, at $10 to $20 per acre, are both […]