Beach Plum

Size, growth and what to expect

On the dunes beach plum forms low, spreading thickets 4 to 8 feet tall, and the USDA plant guide notes that a well-tended inland shrub can reach 18 feet. Thickets spread up to 20 feet across. It grows at a medium pace, roughly a foot and a half a year in its youth on an average site, which is the rate our growth estimator uses for it.

Planted stock can bear from its third year, by the Rutgers account, with harvest from late August into October. A heavy crop is often followed by a light one. White flowers half an inch across open in April or May before the leaves. The fruit is a cherry-shaped plum half an inch to an inch across, usually dark purple, and its flavor runs from sweet to tart or bitter from bush to bush. Birds and small mammals take the fruit and shelter in the thickets.

It grows wild on the older dunes of the Atlantic coast from the Canadian Maritimes south to northern Virginia.

How to grow Beach Plum

Beach plum wants full sun and sandy, fast-draining soil, and it grows well inland. It stands up to salt spray, wind and drought, and it rots in heavy, wet ground. It fits a dune, a dry bank or a roadside, spaced 6 feet apart.

Plant bare-root saplings while dormant, early spring or after leaf drop. Dig a hole twice the width of the roots and no deeper, set the root flare at grade, and backfill with the sand or soil you removed. Mulch lightly, two inches, kept off the stems. Sow pits in fall two inches deep under hardware cloth against mice.

Water once a week through the first summer, then rarely. Rabbits and voles chew the bark and deer browse the shoots, so use a wire guard for the first two or three years. Prune in late winter only to remove dead or crowded wood.

Beach plum needs a second, unrelated seedling nearby to set fruit. Fruit ripens in late August or September. Plum curculio and brown rot can take the crop in humid years. Seedlings bear within about four years.