The initial recommendation contains enough nitrogen for the first year. In subsequent years, follow one of the maintenance schedules for commercial orchards. Lush vegetative growth and little or no yield usually indicate excessive application of nitrogen. Reduce nitrogen fertilization if new terminal growth of tree limbs exceeds 12 to 18 inches per year. Uptake of micronutrients by plants decreases as soil pH increases.
Micronutrient availability can be difficult to assess from a soil test alone, especially for zinc.
If you suspect a micronutrient problem, collect matching soil and leaf samples. Take such samples only when abnormal growth or symptoms appear. Take soil samples from around the perimeter of the tree to a depth of 6 inches, staying within the drip line. Collect recently matured leaves from branches of current year's growth. You can send soil and plant tissue samples to the Agronomic Division laboratory.