Plum trees belong to the Rosaceae family, which also includes apple, peach and cherry trees. These trees produce edible fleshy fruits used for making pies, jams or for eating on their own. Plum tree varieties can be found from U.S. Department of Agriculture plant hardiness zones 3 through 9, where they are cultivated for their beautiful spring flowers and tart fruits. Simple-leafed trees look alike, so it is hard to tell a plum from a cherry tree, especially when neither is producing fruit. To identify a tree in your yard, that may be a plum, there are a few steps to help you distinguish it from other trees.
Plum trees fall into two major categories -- ornamental plums and fruiting varieties. Ornamental plums are cultivated for their flowers. Even though they may produce fruits, they are usually small and only good for making jam. Fruiting varieties are cultivated for fruit production. They have large, fleshy fruits which can be eaten like a peach. Some fruiting trees require a pollinator tree in order to produce fruit. Both varieties can be found throughout the United States and Canada.
The bark of plum trees is similar to that of cherry trees. It is dark in colour, but has no horizontal lines. The young branches are hairy but become scaly with age. Young trees have smooth bark, which also becomes scaly with age. Most non-dwarf varieties can grow up to 30 feet tall and have spreading crowns. Dwarf varieties can grow up to 20 feet tall.
Plum trees have simple leaves that are round or oblong with toothed margins. The leaves are alternately attached to the tree's branches with a short leaf stalk. The tree is deciduous, which means it loses all of its leaves in the fall and sprouts new one in early spring.
The blooms are white with red-to-yellow sepals that form in the centre of the flower. They spout in groups of two to four with each bloom attached to its own stem. They have five petals that are often odourless or have a foul odour. The overall bloom measures about 1/2 to 1 inch in diameter.
Plum trees produce a round fruits that range in size from the size of a grape to the size of a tennis ball. Small plums from ornamental trees are not palatable to eat fresh but can be used in jams or jellies. The plums are red to yellow in colour and are often coated in a white film. The fruits contain a hard pit seed that is surrounded by a red or yellow flesh. The flesh is soft and tart with some plums having sweet flesh. The fruits hang down below the branches on short stems.