Petiole sampling at bloom helps determine vine nutritional needs. Sample the leaf petioles opposite flower clusters.
General nutrition publications and resources:
- Grapevine Mineral Nutrition, Pete Christensen's PowerPoint gives deficiency symptoms, tissue levels, and correction recommendations.
- Considerations for Monitoring Grapevine Nutritional Status, Stephen Vasquez, UCCE Farm Advisor, Fresno County & Matthew Fidelibus,
UCCE Specialist, UC Kearney Agricultural Center.
- Monitoring and Interpreting Vine Mineral Nutrition Status for Wine Grapes, Peter Christensen, Extension Viticulturist, Emeritus, Department of Viticulture and Enology, University of California, Davis and Kearney Agricultural Center, Parlier
- Use of Tissue Analysis in Viticulture, Instructions for how to sample petioles and reference tissue levels.
- Mineral Nutrition and Fertilization, Chapter from the Raisin and Table Grape Production Manual.
- Vineyard nutrient needs vary with rootstocks and soils
- Selected Commercial Laboratories in Northern California
- Boron deficiency in grapes, Summarized from “Grapevine nutrition and fertilization in the San Joaquin Valley.”
- 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.
- Magnesium Deficiency Becoming More Common, UC Cooperative Extension Tulare County
- Managing phosphorus deficiency in vineyards, 1999. Practical Winery and Vineyard.
- Zinc Deficiencies in Grapes, L.R. Wunderlich, Farm Advisor, UCCE Central Sierra
- Grapevine response to concentrate and to dilute application of two zinc compounds, 1978. American Journal of Enology and Viticulture.
- Foothill Vineyard Post Harvest Activities: FERTILIZING, L.R.Wunderlich, Farm Advisor, UCCE Central Sierra