Petiole sampling at bloom helps determine vine nutritional needs. Sample the leaf petioles opposite flower clusters.
General nutrition links:
- Grapevine nutrition-Pete Christensen's powerpoint gives deficiency symptoms, tissue levels, and correction recommendations.
- Use of Tissue Analysis - Instructions for how to sample petioles and reference tissue levels.
- Nutrition information on the Integrated Viticulture website.
- Mineral Nutrition and Fertilization - Chapter from the Raisin and Table Grape Production Manual.
- Vineyard nutrient needs vary with rootstocks and soils.
- Selected Commercial Laboraties in Northern California
- Fall foliar sprays prevent Boron deficiency symptoms in grapes. 2006 California Agriculture.
- Drip irrigation can effectively apply Boron to San Joaquin Valley vineyards. 2005. California Agriculture.
- Boron deficiency in California vineyards. 1960. American Journal of Enology and Viticulture.
- Boron deficiency in grapes. Summarized from “Grapevine nutrition and fertilization in the San Joaquin Valley.”
- Magnesium Deficiency Becoming More Common. UC Cooperative Extension Tulare County
- Managing phosphorus deficiency in vineyards. 1999. Practical Winery and Vineyard.
- Grapevine response to concentrate and to dilute application of two zinc compounds. 1978. American Journal of Enology and Viticulture.