On Oct 8, 6:32 pm, "
wrote:
I have some triple super phosphate i want to use around my
established fruit trees to help them harden off for the winter. There
aren't any application rates mentioned on the bag so i don't know how
much to use. Most fertilizer app. rates are calculated by using x
amount based on the diameter of the trunk measured about 2 feet above
the soil line,but not sure if this also applies to triple super
phosphate. I live in Southern Calif. where soils are on the alkaline
side. How much can i use w/o over doing it? Thanks.

Apply at the rate suggested by the results of your soil test. Contact
your extension center, soil tests are generally very inexpensive.

Otherwise you are just guessing.