The Plum is widely cultivated throughout the U.S., since there are varieties suitable for growing in every state. Plums are extensively grown for commerce in Oregon, Washington, California and Idaho. Trees may have erect or spreading growth, depending on the variety. The leaves vary in shape, also, but are usually egg-shaped with finely serrated edges. The fruits are oval or round having smooth, thin skin. The flesh may be purple, blue, red, green or yellow, also depending on the variety. There are more than 2,000 varieties of Plums available. Many Plums bear fruit as soon as three years after planting. Plums may be eaten fresh, preserved in jellies or jams, dried as prunes, juiced, or fermented as a liqueur.
Plums come from three different backgrounds: American, European, and Japanese.
- Japanese plums have sweet flesh that is somewhat tart near the pit. Japanese plums are usually clingstone, which means the flesh sticks to the pit. These plums grow well where peaches flourish, tolerate heat and need only a short period of winter dormancy. However, these trees bloom at the first touch of warm weather, making them susceptible to damage from late spring frosts.
- European plums are hardier than Japanese plums. European varieties include the late-season prune plums, which are great for drying and eating fresh, and the Gage types, small, greenish fruits valued for their light sweetness. European plums are ordinarily freestone, which means the flesh easily separates from the stone, making canning easy. Many varieties of the European plum will bear fruit with only one tree planted, though the crop will be heavier with a pollinator. European plums also bloom later than Japanese plums, making them ideal for regions with fickle spring weather. Since these plums ripen late (from September to October), a long growing season is needed.
- American plums include the beach Plum, the Canada Plum, the American plum, and the Sierra or Klamath plum. Most of these plums are very cold hardy and tolerate heat and drought. The small plums of these trees vary in quality from one tree to another, but are delicious eaten fresh as well as in jellies, preserves, wines, and liqueurs.