Crabapple trees are closely related to apple trees. They produce tiny fruit that is sour. The fruit of crabapple trees is sometimes made into pies or jams and jelly, but the trees are primarily used for ornamental flowering fruit trees in landscapes, and in orchards to cross-pollinate apple trees. Like many trees, crabapples may be improved with careful pruning.
Most trees including crabapple trees should undergo a severe pruning to shape them when they are first planted in spring. Crabapples that are shaped when they are young seldom need severe pruning as they grow. Instead additional pruning is largely confined to maintenance pruning. Early pruning should remove branches that grow at weak angles. These branches are more likely to break under stress caused by ice or high winds. Branches should be evenly spaced throughout the tree so that they do not crowd one another. Any branches that cross one another or rub should be removed as well as any branches that grow inward. Remove branches that grow straight up and bear few flowers, these branches are called water sprouts. Plant and prune crabapples before 1st June.
As a crabapple grows, it produces tiny offshoots from the trunk below the canopy. These offshoots are known as suckers. Suckers are produced as a reaction to the crabapple tree being grafted onto apple root stock or because the tree has been planted too deeply in the ground. Sucker growth is weak, but usually it diverts nutrients from the canopy of the tree. If left alone, suckers can develop into secondary tree trunks. The flowers and fruit on suckers may be of a different colour and type than on the crabapple trees. Suckers may be pruned from crabapple trees at any time.
Crabapple trees should be pruned immediately at any time of the year to remove damaged, broken or diseased limbs. Prior to pruning, the cutting tools should be sharpened and sterilised in a solution of bleach using one part bleach and nine parts water. When diseased limbs are being pruned, the cutting implements should be sterilised between each cut to halt the spread of the disease to healthy tissue.
Occasionally crabapple tree owners prune a tree to remove a wayward branch or to open the centre of the tree's canopy and let light into the tree. Maintenance pruning should be performed either before flowering or leafing in early spring or after the trees have bloomed in late spring. All pruning of this nature should be perfomred before 1st June. Between June and July, crabapples set buds for flowers that will bloom the following year. Pruning crabapple trees at this time removes all of these flowers.