Today, I fertilized my pecan orchard (photo above). The soil had finally dried up enough so I could run over the orchard with tractor and fertilizer buggy without making tire ruts. In addition, the weather forecast calls for a light rain shower that should be perfect for melting fertilizer pellets into the soil.
This fall I decided to start a new fertilizer program to help build the overall fertility of my orchard soil. Most of my pecan trees are growing in a Hepler silt loam. This soil is excellent for pecan trees but lacks the natural fertility I was accustomed to when caring for the trees growing on Osage silty clay at the Pecan Experiment Field. I applied a fertilizer mix that included not only nitrogen but also included phosphorus and potassium. In total, I spread 55 lbs./ ac. N, 23 lbs./ ac. P and 30 lbs./ac. K. The fertilizer mix I used was 2 parts urea, 1 part di-ammonium phosphate and 1 part potash. I spread 200 lbs of this mix per acre.
The amounts of applied P and K are fairly low but I'm thinking that over time, with repeated applications, I should be able build up the levels of these nutrients in my soil. A more fertile soil will provide a more optimum environment for pecan trees but will also increase the growth of ground cover plants. Since I mow the ground cover regularly, increased ground cover growth translates into increased amounts of organic material added back to the soil. And, organic matter is critical for a healthy soil. Organic matter increases soil aeration, soil water retention, and micro-nutrient availability.
A large part of my orchard was created by allowing volunteer pecan trees to grow up in an abandoned farm field. As these trees grew, I grafted them to northern pecan cultivars. As a result, I have a mixed-aged orchard that includes young, bearing trees along with newly grafted saplings (photo above). When it comes to fertilizing, I broadcast over the entire acreage. Sure, the small trees would probably grow just as well with a spot treatment of fertilizer but I go back my objective for fertilizing this Fall. I am striving to build soil fertility and that means the fertility of the entire pecan grove.