For example, N levels will be higher because of severe pruning regardless of fertilizer program. This should be considered if the orchard was or is planned to be heavily pruned. Moisture supply before sampling can also effect nutrient levels. Dry conditions will usually result in lower N and K and higher Mg in leaf tissue. Spray application of Mg, micronutrients or pesticides containing nutrients, will raise the level of these nutrients found in leaf tissue.
Information concerning soil texture, drainage and cation fixing capacity is important.
System of soil management, past fertilizer program, growth, foliage color, crop history, fruit quality and storage life are all important and should be considered when interpreting leaf analyses data in terms of changes to fertilizer programs. The balance between nutrients should be carefully examined. For example, increasing K rate when Mg is low may cause Mg deficiency. An increase in N when K is low may result in K deficiency. N might be applied since pruning would have increased leaf N concentrations.