Updated: May 8, 2019
Several recent soil analyses around Knoxville have shown trace amounts of Phosphorous (P) and Potassium (K). Phosphorous is critical for a variety of cell and organ functions in plants. Deficiencies in P, especially in cherry and other stone crops can cause poor fruit production and slow growth. Limited potassium (K) can cause discoloration (purpling and/or bronzing) of leaves and a 'warped' fruit. These responses to a lack of K in the soil are similar to responses to various pests. Potassium is also critical to proper functioning of a plants' immune response. Without sufficient K, plants will catch every passing 'cold'.
One way to differentiate pests (or biotic) causes from nutrient (abiotic) causes is to look at growth-rate. Growth-rate can be measured by comparing this seasons internal leng