Trees that reliably produce white flowers during the spring months include native and non-native species. The cold hardiness of these flowering trees determines where in North America you can use them in North America, with several non-native varieties suitable for a wide range of potential sites. The white flowers turned out by these trees make them useful as specimen trees, with the size of the tree a major consideration in how and where you situate it.
The Callery pear (Pyrus calleryana) is a tree of Korean and Japanese origin that blooms in spring, producing abundant white flowers. The flowers often arrive before the leaves do, leading to an attractive display that helps landscapers overlook some of this tree's shortcomings. The Callery pear is susceptible to storm damage due to the habit of its branches, and the University of Connecticut Plant Database notes that older trees often split. Nevertheless, the Callery pear, which grows to 40 feet, has a size and shape that make it appropriate for smaller landscapes from U.S. Department of Agriculture hardiness zones 5 through 9.
Plant the horsechestnut (Aesculus hippocastanum) away from sidewalks and driveways; the falling fruits can damage cars or create a littering problem. Horsechestnut is native to Albania and Greece, but after its introduction to America, it escaped from cultivation and now grows throughout USDA zones 4 through 7. Horsechestnut flowers in clusters during mid-May, with each white flower having some yellow and red at its base. Horsechestnut grows over 100 feet in the wild, but most cultivated landscaping specimens stay between 50 and 75 feet. Spiky husks enclose the nuts of the horsechestnut, which is suitable as a shade or specimen tree.
Parts of West Virginia south through northern Florida and westward to southeastern Oklahoma are the native range of the Carolina silverbell (Halesia tetraptera) . The flowers on this 30- to 40-foot-high tree grow in clusters of up to five. Shaped like bells, the white flowers open in early May. Carolina silverbells show up well against a darker background, and the tree is a good fit for planting alongside rhododendrons. Carolina silverbell has a distinct preference for acidic soil.
The bloom period of the singleseed hawthorn (Crataegus monogyna) is fleeting, with the white flowers emerging in May and lasting from a week to 10 days. Singleseed hawthorn, a European and western Asian species, grows to 30 feet, with the branches having a somewhat drooping appearance. Singleseed hawthorn's flowers develop during the summer into a reddish fruit. Birds flock to these trees to devour them. The long thorns that develop along the stems make this species suitable as a barrier or as a hedge. Singleseed hawthorn grows well in full sunshine and in damp sites with solid drainage.