A:       I am not sure what a "self-reliant" tree is. The term "self-reliant" used in this way is new to me. In my experience all fruit trees need proper care and some supplemental fertilization if they are to remain healthy, vigorous and productive over many years. An exception may be legume species plants which fix their own nitrogen from the air, thus are not dependent on the nitrogen present in the soil. Even legumes, however, may become deficient in other nutrients which then need to be supplied by adding fertilizers.

       The sandy soils prevalent in many locations on the Central Coast are very poor in their nutrient content and must be augmented with organic matter and/or fertilizers to grow good crops. A four-year-old persimmon is just reaching maturity, and larger crops of persimmons may be expected in the coming years if the tree is maintained in good vigor.

       A mature persimmon tree requires about one pound of actual nitrogen (N) per year. Therefore, enough fertilizer must be applied to deliver one pound of N per tree per year. If you have a fertilizer that is 15% N, you must apply 6.6 pounds of this fertilizer per tree per year to deliver one pound of N.

       Applications of fertilizer should be divided into at least two applications, one in the spring, and one in the fall. On our sandy Central Coast soils 3 to 4 applications made through the growing season are recommended so the fertilizer is not lost to leaching down past the root zone. Make the first application in late February/early March as the tree wakes up from winter dormancy. Apply the last dose in late October as the tree leaves begin to turn color. Space the other one to two applications at equal intervals in between.