Vineyard Nutrient Management
Macronutrients and Micronutrients
Grapevine development is limited if a nutrient is not available in sufficient quantities resulting in characteristic changes in leaf or shoot color, shape, or growth patterns. The major macronutrients that play an essential role in vegetative and fruit development for grapevines include nitrogen (N), phosphorous (P), potassium (K), magnesium (Mg), calcium (Ca) and sulfur (S). There are a number of micronutrients (also called trace elements) that are essential which include zinc (Zn), boron (B), molybdenum (Mo), manganese (Mn), iron (Fe), and copper (Cu).
Climate Change and What it Means to for Grapevine Nutrition
Evidence suggests that climatic conditions are changing and will continue to do so, resulting in higher average temperatures and rates of evaporation, reduced rainfall and runoff with greater seasonal variability, and more frequent extreme weather events. With respect to grapevine nutrition, changes in temperature and evaporation are likely to affect the availability of soil water to the vines as well as the internal mechanisms of water movement through the vine.
Seasonal Variations in Nutrients
Nutrient element concentration changes throughout the growing season as shown in Table 16.5. The more consistent in the timing of sample collection, the more valid the comparison of elemental concentration from year to year.
For optimum growth, it is not enough to simply have an abundance of available nutrients. Grapevine nutrients also need to be made available in the correct ratios to one another (See Table 16.6). This is because certain elemental fertilizer ions compete with others for uptake. Most fertigation mixes try to achieve a balance between these competing elements.
Click on the following topics for more information on vineyard nutrient management.