Prunus maritima, beach plum, is a deciduous shrub in the Rosaceae (rose family) native to coastal areas of the northeastern U.S., from Maine to Virginia. Its plums are edible, but are quite tart and acidic, so they are generally used for jams and jellies. This species is used for coastal stabilization, to slow the erosion of sand dunes; in natural settings, it is an important food source for coastal wildlife. Although native to coastal areas, it can grow inland, and is sometimes cultivated for its fruit; several horticultural varieties have been developed.
Beach plum typically grows to around 2 m (6 ft) tall and has straggling or prostrate lower branches, although when grown inland may develop tree, rather than shrub, form, and reach heights up to around 8 m (18 ft). Branches occasionally have spines. Leaves are oval to elliptical, usually serrate (with sharp teeth) or crenate (wavy-margined), 2.5 to 6.5 cm (1 to 2.5 in) long, usually pubescent (with short downy hair) on the underside. The 5-petalled white flowers are small, around 1 cm (less than 0.5 in) in diameter, and generally occur in clusters of two or three. Fruits are spherical to oval drupes, with firm, somewhat juicy flesh and a hard pit. Fruits range in color from red to purple (one horticultural variety is yellow), and are covered with a waxy bloom.
Two naturally occurring varieties grow along the Atlantic coast in the Northeastern U.S., and both are listed as endangered: var. maritima is recognized as an endangered species in Maine, Maryland, Pennsylvania; and var. gravesii is listed as endangered in Connecticut.
(Bailey et al. 1976, Everett 1981, Hedrick 1919, USDA 2002.)
On sand dunes beach plum will reach heights of 4 to 7 feet; but if this species is moved inland, and it can attain heights of 16 to 18 feet. When maximum heights have been reached, stem diameter will range from 4 to 8 inches at the root collar. The root system penetrates deep into the soil, and as lower branches are covered by shifting sands, adventitious roots develop. Colonies formed from this layering effect can expand up to 20 feet.
The egg shaped leaves of beach plum are firm, alternate, and dull green; they are rough and ridged above, paler and finely hairy beneath. The leaves are half as wide as they are long, measuring 1½ to 2½ inches long; each leaf is attached to the branches with a stout, hairy, often granular stalk. The leaf edges are finely serrated, with broadly triangular to semi-circular shaped, abruptly pointed teeth.
In April to early May, flowers emerge before the leaves. Each snowy white flower measures ¼ to ½ inch across, with very hairy stalks and sepals. Flowers develop in axillary clusters of two or three. After pollination occurs by bees or wind the flowers become pinkish in color. The edible fruit that develops is round and ½ to ¾ inches in diameter. The color may vary from a purplish-black to red; there are some plants that produce yellow fruit. The fleshy fruit’s surface is covered with a tough skin which has a heavy, white waxy residue. Each fruit contains a single stone type seed which is egg shaped, swollen, and squared-off at the base.
Regularity: Regularly occurring
Global Range: Atlantic coast of North America, from Maryland north to Maine.
Distribution and adaptation
Although indigenous to the mid-Atlantic coastal region, beach plum has been planted successfully on more inland sites. It is well adapted to droughty sites with moderately fertile, slightly acidic, loamy and sandy soils. Beach plum does not perform well on heavy clay soils, but will tolerate moderately well drained conditions.
Beach plum is distributed throughout the Northeast. For a current distribution map, please consult the Plant Profile page for this species on the PLANTS Web site.
Comments: Coastal sand dunes and barrier islands, esp. in the interdune shrub zone.
Quality seedlings are easily produced in nurseries on raised beds. Fall sowing works best to utilize natural stratification forces to break seed dormancy. If spring sowing is selected, the seed must be exposed to a cool moist stratification for at least 30 days, prior to planting. Due to the expansive root system which rapidly develops, seedlings are distributed as 1 year old bare-root or containerized stock. Controlling competing weeds through the establishment period is critical to good survival and performance of the seedlings. Mulching, hand cultivating, and no fertilization for the first year or two are the most effective means of avoiding weedy growth. Application of fertilizer can initiate excessive growth of competing grasses. Once this shrub is established it requires little or no maintenance.
Number of Occurrences
Note: For many non-migratory species, occurrences are roughly equivalent to populations.
Estimated Number of Occurrences: 81 to >300
Comments: Hundreds, but many sites now developed. Only a few dozen large (several miles) coastal barrier dune systems remain.
National NatureServe Conservation Status
Rounded National Status Rank: N4 - Apparently Secure
NatureServe Conservation Status
Rounded Global Status Rank: G4 - Apparently Secure
Reasons: Restricted range, destruction of about half its rangewide habitat, fragmentation of remainder, difficulty of long-term management outside large natural or seminatural barrier dune preserves. Yet, dozens of stands extant in managed areas.
Please consult the PLANTS Web site and your State Department of Natural Resources for this plant’s current status (e.g. threatened or endangered species, state noxious status, and wetland indicator values).
Comments: Habitat intensely used for coastal resorts and recreation.
Biological Research Needs: Response to trampling and saltwater overwash may need study.
Cultivars, improved and selected materials (and area of origin)
There is one variety available on the commercial nursery market for conservation uses named ‘Ocean View’ (composite from plants in DE, NJ, MA). This cultivar was developed and released in 1992 by the Cape May Plant Materials Center, in Cape May Court House, NJ. Foundation seed and orchard stock can be acquired from the PMC by commercial producers. Common stock material of locally collected sources can be purchased from nurseries.
Chemical control of mildew and aphids is sometimes necessary with beach plum, if an infestation becomes excessive.
Relevance to Humans and Ecosystems
Beach plum is most useful in the secondary stabilization and restoration of coastal sand dunes. On Cape Cod, MA, efforts are being made to develop and promote the commercial fruit production of this native plum. This native shrub is utilized by coastal wildlife.
Prunus maritima (Beach Plum) is a species of plum native to the East Coast of the United States, from Maine south to Maryland. Although sometimes listed as extending to New Brunswick, the species is not known from collections there, and does not appear in the most authoritative works on the flora of that Canadian province.
It is a deciduous shrub, in its natural sand dune habitat growing 1–2 m high, although it can grow larger, up to 4 m tall, when cultivated in gardens. The leaves are alternate, elliptical, 3–7 cm long and 2–4 cm broad, with a sharply serrated margin. They are colored green on top and pale below, becoming showy in the autumn. The flowers are 1-1.5 cm diameter, with five white petals and large yellow anthers. The fruit is an edible drupe 1.5–2 cm diameter in the wild plant.
A plant with rounded leaves, of which only a single specimen has ever been found in the wild, has been described as Prunus maritima var. gravesii (Small) G.J.Anderson, though its taxonomic status is questionable, and it may be better considered a cultivar Prunus maritima 'Gravesii'. The original plant, found in Connecticut, died in about 2000, but it is maintained in cultivation from rooted cuttings.
The plant is salt-tolerant and cold-hardy. It prefers the full sun and well-drained soil. It spreads roots by putting out suckers but in coarse soil puts down a tap root. In dunes it is often partly buried in drifting sand. It blooms in mid-May and June. The fruit ripens in August and early September.
Cultivation and uses
The species is grown commercially for its fruit to a small extent, used to make jam. It can be eaten out of hand and usually is a sweet snack although it is much smaller in size when compared to the longer cultivated Asian varieties found in the supermarket. A number of cultivars have been selected for larger and better flavored fruit, including 'Eastham', 'Oceanview', 'Hancock' and 'Squibnocket'.
The species was first described by Marshall in 1785 as Prunus maritima, the 'Sea side Plumb'. A few sources cite Wangenheim as the author, though Wangenheim's publication dates to 1787, two years later than Marshall's.
Plum Island, Massachusetts and Plum Island, New York are named after the Beach Plum; as are Plum Cove Beach in Lanesville, Gloucester, Massachusetts; and Beach Plum Island (State Park) in Sussex County, Delaware.
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- "The Plant List: A Working List of All Plant Species". Retrieved January 27, 2014.
- Germplasm Resources Information Network: Prunus maritima
- USDA Plants Profile: Prunus maritima
- Hinds, Harold R., 2002, Flora of New Brunswick, 2nd ed., Fredericton, New Brunswick.
- Maine Department of Conservation Natural Areas Program: Prunus maritima (pdf file)
- Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan ISBN 0-333-47494-5.
- Center for Plant Conservation: Prunus maritima var. gravesii
- University of Connecticut: Prunus maritima 'Gravesii'
- Cornell University Department of Horticulture: Beach Plum
- University of Connecticut: Prunus maritima
- Preston, Marjorie. "To save coastal dunes, here’s a plum good idea" in Shore News Today (20 October 2010). Retrieved 5 May 2013.
- Marshall, H. (1785). Arbustrum Americanum: The American Grove, Or, An Alphabetical Catalogue of Forest Trees and Shrubs, Natives of the American United States, Arranged According to the Linnaean System, p. 112. Joseph Crukshank, Philadelphia. Downloadable Google Books at .
- Grier, N. M., & Grier, C. R. (1929). A List of Plants Growing Under Cultivation in the Vicinity of Cold Spring Harbor, New York. American Midland Naturalist 11: 307-387.
Names and Taxonomy
Comments: As treated by Kartesz (1994 checklist and 1999 synthesis), Prunus maritima has two varieties: the questionably distinct var. gravesii, known from a single site in Connecticut, and var. maritima, the remainder of the species. Larry Morse, 9/9/99.
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