Fertilizing - After young apple trees have been in place in the yard for a year, they can be fertilized annually. In the spring before the leaves pop, sprinkle a slow-acting, general purpose granular fertilizer on the soil under the tree out as far as the branches reach (the drip-line). If a standard tree grows 8 to 15 inches at the branch tips over the season, it is receiving adequate fertilizer. Branch growth on a dwarf or semi-dwarf of 6 to 10 inches indicates a healthy growth rate and proper fertilization.

Spray program –When the buds show green tissue, spray lime sulfur (2 ounces per gallon of water) to prevent fungal diseases. Do not apply lime sulfur within 3 weeks of a dormant oil spray on the same tree. At the same time you apply the lime sulfur, spray the tree with insecticidal soap (3 ounces per gallon of water) or neem oil soap to control aphids and scale.

When blossom buds are in open cluster, beginning to open and show pink, apply a sulfur-based spray (1 ounce per gallon of water), but not lime sulfur, to fight fungal disease. Use a surfactant or insecticidal soap or neem oil soap with the sulfur-based spray to make it stick better and to control aphids (add 3 ounces of soap per gallon of spray). Do not apply lime sulfur when the tree is in blossom. In addition, spray trees with Bacillus thuriengensus (BT) (1 tablespoon per gallon of water) to kill pest caterpillars. Do not mix a sulfur-based spray with BT. Seven days later, during pink bud to early flower bloom, repeat the sulfur-based spray and the BT spray.

During the period of full bloom, you normally should not spray trees with any fungicide, but if precipitation occurs when temperatures are higher than 60°F, you may apply a sulfur-based fungicide (1/2 ounce per gallon water). You can spray trees with BT (2 ounces per gallon of water) to control pest caterpillars at this time. Use a surfactant with the sulfur, but do not mix BT into the sulfur spray.

At flower petal fall, seven days after full flower bloom, apply a sulfur-based spray (1 ounce per gallon of water), and spray with BT (2 ounces per gallon of water) for pest caterpillars. Again, use a surfactant with the sulfur but do not mix BT into the sulfur spray. Seven days after petal fall (at first cover), repeat the sulfur and BT sprays, and then repeat it again 7 days later (at second cover).