Culture
Best grown in organically rich, neutral to slightly acidic, medium moisture, well-drained soils in full sun to part shade. Appreciates a root-zone mulch to help retain soil moisture. Also appreciates a location protected from strong winds, but avoid warm southern exposures which may promote premature bud opening in spring. Fleshy root system is easily damaged during transplanting, so it is best to select a landscape location carefully and leave this magnolia undisturbed once planted. Prune as needed immediately after flowering. Usually requires little pruning other than removal of dead or damaged branches.
'Susan' is a late-blooming magnolia that is less apt to suffer frost damage in spring.
Noteworthy Characteristics
The genus Magnolia consists of about 100 species (plus numerous additional hybrids and cultivars) of deciduous or evergreen trees and shrubs. Most plants feature large simple leaves and showy, sometimes fragrant flowers (yellow, white, pink or purple) which bloom in early spring before or while the leaves are emerging or in late spring to summer when trees are fully leaved.
Genus name honors Pierre Magnol, French botanist (1638-1715).
'Susan' is a cross between M. liliiflora 'Nigra' and M. stellata 'Rosea'. It is part of the Little Girl series ('Ann', 'Betty', 'Jane', 'Judy', 'Pinkie', 'Randy', 'Ricki' and 'Susan') of hybrid magnolias that were developed at the National Arboretum in the mid-1950s by Francis DeVos and William Kosar. Plants in this series flower about 2-4 weeks later than M. stellata and M. × soulangiana, thus reducing the risk of damage to flowers from late spring frosts. 'Susan' is primarily noted for its compact shrubby habit, slightly fragrant, fuchsia flowers and late bloom (mid-April to early May). It is a slow-growing, deciduous shrub or small tree that typically rises over time to 8-12' tall with an equal spread. Goblet-shaped flowers, each with 6 slightly twisted tepals, bloom shortly before the foliage begins to appear. Flowers (to 5" wide) are purple-red or fuchsia, with paler tones inside. Flowers may sporadically repeat bloom in mid summer. Ovate medium green leaves (to 6" long). Leaves turn yellow-bronze in fall.
Problems
Potential disease problems include leaf spots, anthracnose, canker, dieback and powdery mildew. Potential insect problems include weevils, snails, scale, and thrips.
Uses
Beautiful specimen flowering shrub for lawns, foundations, shrub borders or woodland peripheries. May be grown as a tall informal hedge.