There are three basic types of plums: European, Japanese and American. Plum trees are adaptable to a wide range of climates, so there is likely a variety for nearly every garden. Check with your local nursery to find out which varieties are best for your particular area. Popular varieties include Methley, Ruby and Sweet Morris.
For a decent crop of fruit, some varieties of plums need to be cross-pollinated with a compatible variety. At least two trees should be planted within 50' to 100' for best pollination.
Plums do best with at least six to eight hours of full sun a day. They also prefer well-drained soil, so work a thick layer of organic soil conditioner into the top 10" of the planting site.
Many plums are sold as bare-root trees. Shake off any material clinging to the roots and soak the roots in a bucket of water for an hour or two before planting (Image 1). Dig a hole the same depth as the roots and at least as wide as the roots when fanned out (Image 2). Place the tree in the hole and fan out the roots (Image 3). Backfill with soil until the hole is three-quarters full. Water well to settle the soil. Finish filling the hole and water again. Add mulch around the trees.
In the first year or two after being planted, plum trees require regular watering. In early spring, and again in midsummer, feed trees with 10-10-10 fertilizer. Maintain a weed- and grass-free zone of about 3' in diameter around the base of a tree. Prune any suckers that sprout from the base of the tree and any watersprouts that shoot up from branches.
Plum blossoms must be protected from spring frost damage, which can wipe out a year’s crop. If frost is predicted after fruit-bud set, place lightweight fabric over the tree to form a tent. Add a small heat source such as a light bulb on an extension cord.
Some plum trees must be thinned in order to produce a decent crop of fruit and to prevent branches from breaking due to excessive weight. When the fruits are about the size of a penny, remove enough so that no two plums are closer than 5". Remove the smallest fruit and keep the larger ones.
All plums start out green but end up in a vast array of colors. It is important to find out what the final color should be for the variety of plums you grow in order to determine when to harvest your plums. As a general rule, plums are ripe when the flesh gives to slight pressure.
All plums start out green but ripen to any number of colors. It's important to know what the fruit’s final color should be so you know when to harvest. As a general rule, a plum is ripe when the flesh begins to soften beneath gentle pressure.