Poncirus trifoliate - Trifoliate orange
A close relative of the commercially used species of citrus, it is often used as the rootstock for commercial oranges as it imparts some cold hardiness.
Trifoliate orange shows great fall color and winter interest with contorted spiny branches and fruit which holds into the winter. Also check out the cultivar ‘Flying Dragon’ a dwarf variety with even more branch contortion.
Oxydendrum arboreum - Sourwood
Sourwood is an excellent example of rich fall color! With shades of scarlet, maroon, and plum persisting late into the autumn season, Oxydendrum arboretum is a must-see for a fall-color tour of the arboretum!
Franklinia altamaha - Franklina
The Franklinia is a deciduous small tree or large shrub, with elongated, dark green leaves that turn red, orange, or pink in the fall. Its most striking feature is its showy two- to three-inch snow white flowers, with clusters of golden yellow stamens in the centers. The tree flowers from late summer until frost.