The shoot tips in this Columbia Valley Cabernet Sauvignon vineyard are missing, a sign that canopy growth stopped and the shoot tips were burnt off. To understand deficit irrigation, growers must also understand stress management and how to “read” how much moisture is in their soil profile. Managing stress is about timing, intensity, and duration, said Dr. Russell Smithyman of Washington State’s Ste. Michelle Wine Estates. The vine reacts differently to high temperatures in May than in August, just as a few hours of 100-degree temperatures will stress vines differently than several weeks of 90°F temperatures. Smithyman believes that preconditioning […]