The flowering crabapple is a welcome addition to spring landscapes, especially in the North and the Midwest. While surrounding trees are still displaying the barren appearance of winter, the crabapple features intense pink or reddish buds that blossom into delicate pink or white blooms. Crabapples can grow from 6 to 50 feet tall, with most cultivars in the 15- to 25-foot range, and come in a variety of shapes, including spreading, columnar, vase-shaped, weeping--with pendulous branches--and pyramidal. The small, tart apples, which appear in the fall, can be made into jellies and jams.
To ensure that your crabapple survives to the point where you will need to trim it, plant it in full sun in well-drained soil. The crabapple is not picky about pH; soil can be either acid or alkaline, loamy or clay. Your crabapple will probably need little fertilizer the first year, although it's a good idea to put organic compost in the planting hole. However, if the leaves seem disproportionately small and the tree shows a growth of less than 5 or 6 inches a year, that is an indication that you will need to use a nitrogen-rich fertilizer. The crabapple does not need frequent watering, unless drought conditions exist; then, you need to water thoroughly every two to three weeks, moistening the soil to 2 to 6 inches. Drought alone won't usually kill crabapple trees, but the tree will put its energy into surviving, and the floral display will be diminished the following year.
Crabapple Trimming Schedule
The best time to trim (prune) a crabapple tree is in early spring, before the tree flowers and before new growth begins. Don't worry about interfering with flowering--provided you don't over-prune, your tree will still develop plenty of blossoms from the branches you leave. Prevent the introduction of pathogen spores by never pruning your crabapple tree when it is in full leaf. Another reason for pruning when the tree is dormant is that by mid-June to July, next year's flower buds are forming; should you trim them at that time, you will reduce flowering and fruiting for next season.
Crabapple Trimming Techniques
Remove the shoots--also called water sprouts--from the branches, as well as the shoots, or suckers, that grow from the roots or base of the tree. Trim away all dead, damaged, diseased or crossed branches. Suckers and water sprouts should be cut back flush with the trunk, while larger branches should be cut at a wide angle, away from the main stem. Promote good air circulation by pruning the center of your crabapple tree. Don't take off more than 25 to 30 percent of the branches per season; the tree needs a certain amount of leaves for photosynthesis, and over-pruning can promote growth of additional suckers. Be alert for excessive sucker and water sprout growth--this could be a sign that your crabapple tree is in distress.