Gardeners across the American South enjoy mild winters and long, hot and humid summers, typically in U.S. Department of Agriculture hardiness zones 7, 8 and 9. Flowering trees provide color interest in landscapes mainly from early spring to late summer. Exposure to light and winter cold, as well as watering needs varies according to flowering tree species, and even some subtropical trees perform beautifully in coastal southern Texas and peninsular Florida.
Horticulturists at Clemson University in South Carolina recommend trees be planted in the autumn months to take advantage of the cooler weather and moist soils. The plants are heading into dormancy, allowing their root systems to continue growing and establishing across the mild winter months. Container-grown flowering trees may be planted any time of year the soil is workable, but balled and burlapped trees are best planted in autumn; avoid summer planting that adds dry soil and heat stress to the trees. In sandy soils of Florida, consider planting at the start of the summer rainy season as compared to the hot, dry spring months.
While many people assume trees flower only in spring, breaking the dull dormancy and lifeless branches of winter, the climate of the South allows floral displays for several months from early spring to late summer. February and March finds many early flowering trees blossoming, such as star and saucer magnolias, Cornelian cherry, flowering pears, and peaches; dogwoods, redbuds, ornamental cherries and southern magnolia by April. Late spring to early summer brings black locust, princess tree, buckeye, kousa dogwood and stewartia trees into stages of flower. Midsummer is dominated by crape myrtles--in all their dozens of sizes and colors--as well as golden rain trees, swamp cyrilla and sourwood.
Native v. Exotic
Many quality flowering trees are native to the American South and are well adapted to the climate, soils and rainfall regimes of the region. Popular native species include the redbud, flowering dogwood, sourwood, buckeyes and swamp cyrilla. Exotic species, those native to regions outside of the South, also provide substantial ornamental merit as long as they do not become invasive and displace native plant communities. Copious production of seeds from the non-native golden rain tree and princess tree results in weedy volunteers popping up across landscapes and roadsides.
Too often the mildest winter areas of the American South, peninsular Florida and extreme southern Texas, are not included in discussions about flowering trees. In these areas, USDA hardiness zones 9 and 10, many subtropical and tropical trees perform well, handling the intensely hot and humid summers and winters that never or barely reach the freezing point. Lovely trees to consider in these states include species of trumpet trees, jacaranda, Texas olive, Jerusalem thorn, camellias, bottlebrushes and copperpods.
Generally speaking, local garden centers carry flowering trees with a proven hardiness and adaptability to soils and rainfall in your particular area of the South. Examples include the ever-popular redbud, crape myrtle and flowering dogwood. Native flowering trees may be more difficult to locate; seek out native plant nurseries or native plant societies for sources of lesser known tree species, such as swamp cyrilla or sourwood.