American plum

Sun

Full sun gives the best flowering and fruiting; tolerates partial shade.

Water

Moderate; water regularly while establishing. Established plants tolerate short dry periods, but prolonged drought reduces fruit quality.

Soil

Adaptable to sandy, loamy or clay soils with good drainage; tolerates a broad pH range. Avoid permanently wet ground.

Height

15-25 ft (4.6-7.6 m)

Spread

15-25 ft (4.6-7.6 m); suckering colonies can spread much farther.

Flowers

Clusters of white flowers in early to mid-spring, usually before the leaves open.

Foliage

Oval to oblong green leaves with sharply toothed edges; often yellow in autumn.

Growth

Moderate to fast when young.

Care needed

Medium

• Pollinators
• Cold hardy
• Wildlife
• Low allergen
• Fragrant
• Edible

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   7 ft (2 m)

2. After 1 year

   7 ft (2.3 m)

3. After 2 years

   8 ft (2.5 m)

4. After 3 years

   9 ft (2.8 m)

5. After 5 years

   11 ft (3.3 m)

About 16 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Toxic

Native to

the US and Canada

In the garden

Spreads vigorously: plan to contain it.

Growth rate

Fast

• Water deeply during dry spells for the first two growing seasons; thereafter, water during prolonged drought or fruit swelling.
• Spread 2-3 in (5-8 cm) of organic mulch over the root area, keeping it clear of the trunk.
• Plant two genetically different American plums with overlapping flowering times; suckers from one plant do not provide a different pollen source.
• Remove unwanted root suckers promptly, or leave them where a dense wildlife thicket is wanted.
• Feed only if growth is weak or a soil test shows a deficiency; excess nitrogen encourages leafy growth rather than fruit.

Pruning. Train young plants as a single-trunk tree or a multi-stemmed shrub, removing crossing branches and poorly placed shoots. Make routine cuts in dry weather in late spring or summer, rather than wet winter conditions, to reduce disease risk.

Pick plums in late summer to early autumn when they develop their mature yellow, red or reddish-purple colour, soften slightly and detach easily; taste a sample because skin colour varies between plants. The flesh is edible fresh, though often tart, and is useful for preserves; discard the stones. Expect a first useful crop roughly 3-5 years after planting a young tree, with seed-grown plants sometimes taking longer.

Autumn

Plant while dormant where winters are mild, leaving room for the mature crown and suckers.

Early spring

Plant in cold-winter areas once the soil is workable; renew mulch and check watering.

Spring

Watch flowering and pollinator activity; protect visiting insects by avoiding insecticide use during bloom.

Late spring

Check developing fruit for damage and remove fallen or infested fruit.

Summer

Prune in dry weather, remove unwanted suckers and water during prolonged dry spells.

Late summer

Check ripening fruit frequently and harvest as it softens; ripening may continue into early autumn.

Late autumn

Clear fallen fruit and remove dried fruit remaining on branches to reduce disease carryover.

• Use in an informal boundary hedge where suckering growth can form a dense screen.
• Plant at a sunny woodland edge with serviceberries and native flowering perennials.
• Include in a mixed orchard or food forest, keeping access around plants for picking and sucker removal.
• Grow as a small flowering tree in a lawn or meadow, with space around its thorny branches.

Garden styles it suits: Wildlife garden, Native hedgerow, Food forest, Backyard orchard, Edible landscape and Homestead.

Plant it with: Serviceberry, Black chokeberry, Wild bergamot, Purple coneflower, Little bluestem and Butterfly weed.

Wildlife: Flowers provide early pollen and nectar for bees and other insects. Birds and mammals eat the fruit, while dense, sometimes thorny growth provides nesting sites and shelter; the foliage also supports caterpillars of several moths and butterflies.

• Black knot: hard black swellings develop on branches. Cut affected wood well below each knot in dry weather, remove it from the garden and disinfect tools between cuts.
• Brown rot: fruit rots and may remain as dried mummies. Remove affected fruit, clear fallen fruit and thin crowded branches to improve airflow.
• Plum curculio in eastern North America: beetles scar young fruit and larvae cause premature drop. Collect fallen fruit promptly and ask your local extension service about locally timed controls if damage is persistent.
• Poor fruit set: isolated plants, frost during flowering or poor pollinator activity can limit crops. Add a genetically different American plum, choose a site away from frost pockets and avoid spraying flowers.

Leaves, stems and the kernels inside the stones contain cyanogenic compounds and can seriously poison people, cats, dogs and horses if eaten. Wilted leaves are a particular livestock hazard. Ripe fruit flesh is edible, but do not chew or crush the stones; whole stones also pose choking and blockage risks.

Where it spreads. Spreads vigorously by root suckers and can form large thickets in gardens and pastures across its native central and eastern North American range. This is usually a management issue rather than non-native invasion; keep it away from boundaries where suckers would be unwelcome.

• Chickasaw plum (Prunus angustifolia)

  Usually has much narrower, shinier leaves and smaller fruit; American plum has broader leaves with conspicuous, sharp teeth.

• Beach plum (Prunus maritima)

  Usually a lower shrub associated with coastal sand, with smaller, thicker leaves and small purple fruit; American plum commonly becomes a taller inland tree.

• European plum (Prunus domestica)

  Cultivated forms generally have larger fruit, often oval, and less thorny growth. American plum usually has smaller, rounder fruit and a strongly suckering habit; hybrids can make identification difficult.

Prunus is the Latin name for plum, and americana refers to the species' American origin.

Propagation. Grow from cleaned seed given moist cold stratification; seedlings vary in fruit quality. Rooted suckers taken during dormancy reproduce an own-root plant, while grafting preserves selected fruiting forms; suckers from a grafted tree may belong to its rootstock.

Accepted botanical name

Prunus americana

In the US and Canada

Native in Canada and the lower 48 states.

Native range

Alabama, Arkansas, Colorado, Connecticut, Delaware, District of Columbia, Florida, Georgia, Idaho, Illinois, Indiana and Kansas.

Measured

Soil pH 5 to 7. Average height 460 cm.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.