By Mollie Luze
With the spring frost free date fast approaching, gardens throughout the state are abuzz with activity. Along with the tulips and daffodils, one of the first colors of spring is seen in the ornamental crabapples.
Due to its frequent cross fertilizing, the list of crabapple cultivars is extensive with over 400 to 600 different crabapple types grown across the country. The crabapple is part of the Rosaceae family and shares the Malus genus with the table apple. In fact, the only difference between crabapples and the apple species we eat, is fruit size. If the fruit is less that 2” in diameter it is considered a crabapple, while anything larger, considered an apple.
There are few other trees or shrubs that are as impressive as a crabapple in full bloom. The flowers range in shades of white to pink to red with a bloom time anywhere between late April to early June depending on cultivar. The ornamental also has color appeal throughout the summer and fall with varying foliage colors of greens and purples as well as late season red to yellow fruits.
Most forms reach a height of 15' to 25’ at maturity and often have unique branch architecture. In general, crabapples require little pruning, but if any is done it should be completed before early June. Pruning may be done to remove sucker growth and out of place branches and to open the center of the plant to light and air. Since flower buds for the next season are initiated in mid-June, avoid pruning after this time to reach full bloom potential.
Crabapples are adaptable to a variety of soil conditions and do best in well drained, moist and acidic (pH 5.0 to 6.5) soils. For best flower and fruit production, trees should be planted in full sun. One of the most common diseases found in crabapples is fireblight, with the first visible signs consisting of tip dieback on young shoots and bud clusters. Branches are also killed off by sunken cankers that eventually spread into larger branches and trunk. Infected plant material should be removed during dormant, dry conditions with cuts made at least 4” below the canker base. To avoid fireblight as well as other disease and insect problems, make sure to purchase the newer cultivars bred for resistance. Forms from Asia have been found to be especially more resistant than our native crabapples.