Extension Educator, Horticulture
Few ornamental trees offer the variety of tree shapes, sizes, flower colors and ornamental fruit as flowering crabapples. There are over 700 cultivated varieties of crabapples.
Flowering dates range from early April through mid-May. Flower colors range from white, pinks to red. Tree height may be from 6 to 50 feet with most in the 15 to 25 feet range. The varieties vary from weeping, spreading, columnar, vase-shaped to pyramidal which allows many opportunities for use in landscapes.
One of my favorites is 'Snowdrift.' The red flower buds open into single white flowers that cover the tree from late April into early May. The flowers are followed by small orange-red fruit that persists into winter until the cardinals snack on them. 'Snowdrift' shows good resistance to apple scab, one of the more unsightly crabapple diseases.
A nice small crabapple is 'Sargent' with its single white flowers and small dark red fruit. At maturity 'Sargent' is 6 to 8 feet tall and just as wide. In the landscape it is a nice tree for a corner foundation planting. 'Coralburst' is a low growing rounded tree with coral pink flowers and reduced quantities of small rust-red fruit. With its eight feet height, 'Coralburst' fits well into small courtyards and narrow spaces. If you are into formal pruning, 'Coralburst' lends itself well to topiary and espaliers.
'Prairiefire' is a new introduction from the University of Illinois that reaches 15 to 20 feet tall. The dark red flowers, shiny red bark and persistent red fruit make 'Prairiefire' a beautiful addition to the landscape. Before purchasing a crabapple spend some time researching varieties. Avoid older varieties such as 'Hopa,' 'Almey' and 'Eleyi' because of their susceptibility to diseases. Look for trees that are resistant or at least moderately resistant to fire blight, apple scab, cedar apple rust and powdery mildew.
Apple scab is a common disease of crabapples. The severely blemished leaves drop in late summer. Most crabapples will survive apple scab infection, but their ornamental value is reduced. Summer is short enough for me without seeing bare trees in August. Fungicide sprays can be used throughout the spring to reduce infection from diseases such as apple scab, powdery mildew and cedar apple rust, but the sprays must be applied regularly. Fungicide sprays are predominantly protectants against infection. Once trees are infected, fungicides show little effect.
The best control is the use of resistant varieties. Along with disease resistance, look for varieties with small fruit or fruit that persists into winter until the frozen apples shrivel or are eaten by birds. Crabapple fruit size can vary from pea size to golf ball size. Larger fruited varieties are attractive, but the fruit can be messy around patios and sidewalks.
Varieties with small fruit include 'Sargent,' 'Tina,' 'White Angel,' 'Red Jade' and 'Liset.' 'Spring Snow' crabapple has fragrant white flowers and bright green foliage with few to no fruits produced. For more information on crabapple selection, check with your University of Illinois Extension office for the Horticulture Fact Sheet LH-3-80 "Crabapple trees recommended for landscape use in Illinois."
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