Native to a huge expanse of the interior of eastern North American, the American or wild plum tree naturally grows in meadows, along rivers or in sunny openings in woodlands. A slow-growing deciduous tree, it matures to a high of 10 to 25 feet tall and up to 20 feet wide. It supplies food for many insects and birds in its flower, foliage and fruits. Grow American plum in U.S. Department of Agriculture (USDA) winter hardiness zones 3 through 8.
The American plum is usually a multi-stemmed small tree that looks much more like a twiggy shrub than a classical tree. The branches are wide spreading and thin, giving the plant a fine texture in winter when leaves are absent. An important identifying feature of this plum species is that it readily suckers from the roots, creating a thicket of sprouting twigs away from the main trunks of the tree.
Mature leaves of the American plum measure 3 to 4 inches in length, are oval in shape and taper to a sharp point. The leaf blade has many tiny-teeth serrations on its edges. It is a medium green in color with a lighter green underside and in the autumn turns yellow before dropping away. The leaves are arranged in an alternating pattern on twigs.
The American plum blooms in early to mid-spring before it unfurls its foliage. In North America that usually means in April. It also is in bloom when the rest of the native trees are still lifeless and dormant, and this plum can be quickly spotted as a cloud of white on the sunny edges of woodlands. The many fragrant, white, five-petaled flowers appear in lined clusters all along the branches, attracting bees for pollination.
Ripening in mid to late summer, the small drupe fruits are about 1 inch in diameter. Developing only from flowers that were pollinated successfully, the green fruits are partially hidden by the foliage in late spring and summer, but are readily picked by hungry songbirds at any time. When ripe, the plums are red-purple to yellow-brown.
When trees are young, the bark is smooth and reddish gray. As they begin to branch and reach considerable size, the trunk develops brown-gray bark that has irregular ridges and exfoliates in curled strips. Young twigs on large trees are smooth and reddish in color while the lower reaches of the branches often have short, spur or thorn twigs that are no longer than 1 inch in length. In winter, the twigs bear sharply pointed reddish-brown buds.