Beach plum

Photo: Wikimedia Commons — Public domain · source

Survives zone 3 through 7

Harvest calendar

Best planted in early spring after your last frost, or in fall before the ground freezes, depending on your climate.

The beach plum, a true coastal-dune shrub that takes salt wind head-on. Fruit about 15mm, purple-black, and very variable between bushes — sub-acid to sweet — which is why the wild stands are picked selectively and named selections matter. A classic jelly fruit of the north-east American coast.

Hardiness

Zone 3–7

Habit

Shrub

Edible part

Fruit

Ripens

Late Aug–Sept

Mature size

Dense shrub to 2.5 m, medium growth rate

Light

Full sun — will not fruit in shade

Soil pH

5.5–8.0 (mildly acid to mildly alkaline); thrives on pure sand

Environment

Coastal

Native range

Eastern North America — New Brunswick south to Virginia, on light gravelly or sandy soils near the coast.

Status

Both wild and cultivated

Years to fruit

2–4 yrs

Growth speed

30–60 cm/year — medium to fast.

Spacing

300 cm (118 in) apart — about 9 m² (97 sq ft) per plant

Leaf shape

Alternate, oval, 3–7 cm long, finely toothed, dull green above and noticeably downy-grey beneath — a salt- and wind-adapted leaf.

Root system

Shallow and suckering, throwing root shoots that build a thicket over time — the reason wild American plums form dense colonies.

Fruit description

Round plums 1.5–2.5 cm across, ripening deep purple-blue (occasionally red or yellow) under a heavy waxy bloom; tart-sweet with a thick skin, and the classic fruit of North American beach-plum jelly.

Propagation

Suckers lifted in the dormant season are simplest and come true. Seed needs about 90–120 days moist cold stratification at 4°C after the flesh is cleaned off.

Pollination

⚠ Mostly self-incompatible — a beach plum generally cannot pollinate itself and needs another beach plum nearby for a decent set. Plant two or more. Insect-pollinated, chiefly by bees working the dense white spring bloom.

The edible parts listed above are a starting point, not a field guide. Identify a plant with certainty — ideally against a local authority — before eating any part of it, and read the full disclaimer. Spotted something wrong? Report it.