Which nutrient is less commonly fertilized in California agriculture?

Magnesium is less commonly fertilized in California agriculture primarily because the soils in many regions of California typically contain sufficient levels of magnesium to meet the needs of most crops. In particular, California's diverse soil types and climates often support adequate magnesium availability, reducing the necessity for additional fertilization.

Additionally, many common crops grown in California, such as almonds and grapes, are not highly responsive to magnesium fertilization, making it less of a concern for growers. In contrast, other nutrients, such as sulfur, boron, and zinc, can have higher instances of deficiency due to various factors, including soil composition, crop requirements, and environmental conditions. Consequently, while magnesium is essential for plant health, its fertilization needs are not as prevalent, making it a less commonly fertilized nutrient in the state's agricultural practices.