Influence of nitrogen fertilization and other vineyard cultural practices on the

Sauvignon blanc and Chardonnay grapevines grown at the North Oakville Experimental Vineyard (OEV) generally responded favorably to increased rate of nitrogen fenilization up to 90 lbs/acre as demonstrated by higher yield, shoot growth, pruning weight and total leaf area per vine. Differences in fruit composition between low and high nitrogen fertilization were relatively small. However, high N generally increased the pH, TA, malate, K, and arginine levels of must of both cultivars. The field fertilization did certainly improve the ability of the juices to ferment. Without the nitrogen additions, the juices took twice as long to ferment. Otherwise, the routine must and wine analyses show little differences.