How to Care for Semi-Dwarf Combo Apple Trees

Plant your semi-dwarf apple tree in spring. Choose an area that has good soil drainage and where the sun shines at least six hours every day. Dig organic compost into the planting area at the rate of one part compost to every four parts of soil, and make the planting hole about twice the size of your tree’s root system.

Water newly planted and young trees once a week, to equal about one inch of water. As your tree grows larger, keep an eye on soil moisture and water when the soil is dry to the touch.

Fertilize your semi-dwarf combo apple tree with a high nitrogen plant food such as 21-0-0 one month after you plant it by scattering one cup of the fertilizer six inches beyond the trunk in a circular pattern. Repeat this application in early spring and again in April, May and June of the following year. As your tree grows larger, increase the amount of plant food to two cups in year three and three cups in year four.

Thin small fruit when it is one to two inches in diameter to prevent branch breakage and also to increase the size of remaining apples. Leave about four inches between the fruit that you leave on the tree.

Prune your semi-dwarf combo apple tree during its winter dormant season. Cut branches back to the branch collar to maintain a scaffold shape, but take extra care to keep all branches of the different varieties the same size: don't allow a strong variety to dominate the weaker ones. Remove all branches that exist lower than two or three feet from ground level and also remove branches to allow good air circulation. Maintain a strong central leader branch.

Spray your tree with an approved dormant spray in winter to control diseases and insect pests.