American Plum, American Wild Plum, Wild Plum
Prunus americana
Family: Rosaceae
What it is like
Bloom Color: White. Main Bloom Time: Early spring, Late spring, Mid spring. Form: Rounded.
Prunus americana is a deciduous Tree growing to 6 m (19ft 8in) at a medium rate. See above for USDA hardiness. It is hardy to UK zone 3. It is in flower in April, and the seeds ripen in August. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.
Height (m): 6
Where it is found
Rich soils in mixed deciduous woodland, by streams, on the borders of swamps and in hedgerows.
N. America - New York to Florida, extending westwards as far as the Rocky Mountains.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 3
Fruit - raw, cooked in pies etc or used in preserves. The flesh is succulent and juicy, though it is rather acid with a tough skin. The best forms are pulpy and pleasant tasting. The fruit is best cooked, and it can also be dried for later use. The fruit is about 25mm in diameter and contains one large seed. Seed - raw or cooked. Do not eat the seed if it is too bitter - see the notes above on toxicity.
Seed: includes nuts, cereals, peas and beans.
Medicine
Rating: 2
A tea made from the scraped inner bark is used as a wash to treat various skin problems and as a mouth wash to treat sores. A poultice of the inner bark is disinfectant and is used as a treatment on cuts and wounds. The bark is astringent, diuretic and pectoral. It has been used to make a cough syrup. An infusion has been used in the treatment of diarrhoea, kidney and bladder complaints. An infusion of the twigs has been used in the treatment of asthma. Although no specific mention has been seen for this species, all members of the genus contain amygdalin and prunasin, substances which break down in water to form hydrocyanic acid (cyanide or prussic acid). In small amounts this exceedingly poisonous compound stimulates respiration, improves digestion and gives a sense of well-being.
Antiasthmatic: Treats asthma.
Astringent: Produces contraction in living tissue, reducing the flow of secretions and discharges of blood, mucus, diarrhoea etc.
Disinfectant: Used for cleaning wounds.
Diuretic: Acts on the kidneys, promoting the flow of urine.
Miscellany: Various medicinal actions that need more clarification.
Poultice: A moist, usually warm or hot, mass of plant material applied to the skin in the treatment of burns etc.
Other
Rating: 3
A green dye can be obtained from the leaves. A dark grey to green dye can be obtained from the fruit. A red dye can be obtained from the roots. This species is widely used as a rootstock for cultivated plums in North America. The tough, elastic twigs can be bound into bundles and used as brooms for sweeping the floor. Trees often grow wild along streams, where their roots tend to prevent soil erosion. Wood - heavy, hard, close-grained, strong. It weighs 45lb per cubic foot. Of no commercial value because the trunk is too small.
Broom: Used for sweeping the floor etc.
Disinfectant: Plants used for disinfecting.
Dye: Plants that provide dyes.
Miscellany: A rag-bag of items that are difficult to categorise.
Rootstock: Plants used as the rootstock for grafting scions onto.
Soil stabilization: Plants that can be grown in places such as sand dunes in order to prevent erosion by wind, water or other agents.
Wood: A list of the trees and shrubs that are noted for having useful wood.
Espalier: A tree or other plant that is trained to grow flat against a support (such as a trellis or wall).
Food Forest: Plants for Edible Forest Gardens and Food Forests.
How it is grown
Landscape Uses:Border, Espalier, Pest tolerant, Specimen. Thrives in a well-drained moisture-retentive loamy soil, doing well on limestone. Prefers some lime in the soil but is likely to become chlorotic if too much lime is present. Succeeds in sun or partial shade though it fruits better in a sunny position. Trees are probably hardy to as low as -50°c when fully dormant. A fast-growing but short-lived tree in the wild, it is cultivated for its edible fruit in N. America, where there are many named varieties. It flowers well in Britain but rarely fruits well here. Most members of this genus are shallow-rooted and will produce suckers if the roots are damaged. Plants often produce suckers at the roots and form thickets. The branches are brittle. Plants in this genus are notably susceptible to honey fungus. Special Features: North American native, Edible, All or parts of this plant are poisonous, Attracts butterflies, Blooms are very showy. The plant is heat tolerant in zones 8 through 1. (Plant Hardiness Zones show how well plants withstand cold winter temperatures. Plant Heat Zones show when plants would start suffering from the heat. The Plant Heat Zone map is based on the number of "heat days" experienced in a given area where the temperature climbs to over 86 degrees F (30°C). At this temperature, many plants begin to suffer physiological damage. Heat Zones range from 1 (no heat days) to 12 (210 or more heat days). For example Heat Zone. 11-1 indicates that the plant is heat tolerant in zones 11 through 1.) For polyculture design as well as the above-ground architecture (form - tree, shrub etc. and size shown above) information on the habit and root pattern is also useful and given here if available. A sprouting standard sending up shoots from the base. The root pattern is flat with shallow roots forming a plate near the soil surface. The root pattern is suckering with new plants from underground runners away from the plant.
Propagating it: Seed - requires 2 - 3 months cold stratification and is best sown in a cold frame as soon as it is ripe. Sow stored seed in a cold frame as early in the year as possible. Protect the seed from mice etc. The seed can be rather slow, sometimes taking 18 months to germinate. Prick out the seedlings into individual pots when they are large enough to handle. Grow them on in a greenhouse or cold frame for their first winter and plant them out in late spring or early summer of the following year. Cuttings of half-ripe wood with a heel, July/August in a frame. Difficult, if not impossible. Softwood cuttings from strongly growing plants in spring to early summer in a frame. Difficult, it not impossible. Suckers in late winter.
Best place to grow: Woodland Garden Sunny Edge;
Habit: Tree
Hardiness: 3-8
Growth: Medium
Soil: Light (sandy), medium, heavy (clay)
Shade: Semi-shade, no shade
Moisture: Moist
Things to keep in mind
Although no specific mention has been seen for this species, it belongs to a genus where most, if not all members of the genus produce hydrogen cyanide, a poison that gives almonds their characteristic flavour. This toxin is found mainly in the leaves and seed and is readily detected by its bitter taste. It is usually present in too small a quantity to do any harm but any very bitter seed or fruit should not be eaten. In small quantities, hydrogen cyanide has been shown to stimulate respiration and improve digestion, it is also claimed to be of benefit in the treatment of cancer. In excess, however, it can cause respiratory failure and even death.