- One-tenth (0.1) pound of actual N per inch of trunk diameter measured one foot above ground, applied 4-6 weeks before bud swell in the spring should provide the following desired growth per tree: Non-bearing trees – 15 to 30 inches terminal growth. Mature, non-spur trees – 12 to 14 inches terminal growth. Mature, spur type trees – 6 to 10 inches terminal growth with 1/2 to 3/4 inch of growth and 6-10 healthy leaves on non-fruiting spurs. If the previous years growth is not as indicated above, the N rate should be adjusted accordingly. N rates should not be increased after trees reach 8-10 years of age.
- For commercial orchards apply boron annually in the first two cover sprays at the rate of 1.0 pound Solubor per 100 gallons water in a dilute spray. For home orchards, every three years apply one ounce of Borax per inch of trunk diameter measured one foot above ground.
- For commercial orchards, add two to three pounds of calcium chloride or two to four pounds of calcium nitrate per 100 gallons water for at least the last four to six cover sprays. Do not use calcium nitrate on Red Delicious or other nitrate sensitive varieties.