University of California offers multiple online tools to help growers tailor a nutrition plan that fits their pistachio orchard year-round.
Creating a nutrition plan should be an individual exercise based on each orchard. The seasonal plan should consider nutrient deficiencies/toxicity, predicted fertilizer demand and irrigation system efficiency (nutrient uptake), according to UCCE Farm Advisor for Kings and Tulare counties Doug Amaral.
“All growers’ situations are different, so there’s not a single or more common recommendation. It varies from case to case,” Amaral said.
Amaral noted that knowledge of site/soil characteristics, cropping history, cultural practices (irrigation, pruning, etc.), tissue analysis, fertilizer input, plant requirements throughout the season and observation and judgement are all important factors.
Growers have many physical tools at their fingertips to help manage nutrition throughout the season, such as leaf, soil and water reports as well as a general understanding of plant nutrition, but Amaral recommends useful online tools as well.
One tool Amaral recommends is Nitrogen and Potassium Prediction Model for Pistachio for interpreting spring leaf analysis. The model can help growers can respond to pistachio early-season sampling and in-season nitrogen applications to maximize productivity and minimize loss.
Another recommended tool is California Fertilization Guidelines: Pistachio. On the tool’s website, growers will find an interactive display of information and recommendations for nitrogen, phosphorus and potassium, such as general deficiency symptoms, soil testing, leaf analysis and soil and foliar applications.
The last tool Amaral recommended is the Pistachio Prediction Model (PPM), which, according to the website, “uses nutrient analysis of spring leaf samples to predict late summer nutrient concentrations of nitrogen (N) and potassium (K).”