The pomegranate tree (Punica granatum) has been a part of the American landscape since its introduction by Spanish missionaries in the 16th century. Although the tree thrives anywhere that has mild winters, California's climate is responsible for growing the bulk of commercially available pomegranates. Growing to heights of 15 to 20 feet, the pomegranate tree is deciduous and, while dormant, is cold-hardy to 10 degrees F. Early frosts can damage the tree. Pomegranate trees do best in USDA hardiness zones 7 through 10.
Water the pomegranate tree the evening before you fertilize.
Fertilize the pomegranate during the spring, after the tree shows new growth. Sprinkle 2 cups of ammonium sulfite into the soil around the base of the tree, and use a cultivator to scratch it into the soil to a depth of 1 or 2 inches.
Give the tree 4 cups of ammonium sulfite, in the same manner, in the tree's second spring, and 4 cups in the tree's third spring.
Fertilize the pomegranate tree from then on by applying a 3-inch layer of compost or well-rotted manure around the base of the tree, spread to the dripline, each spring.