Content Detail

Blackthorn or sloe is a large deciduous shrub to small tree reaching 9 to 12 feet high with blackish-brown bark and dense, stiff, spiny branches. Native to Europe and western Asia. May be difficult to find in nurseries.

  • Family (English) Rose
  • Family (botanic) Rosaceae
  • Tree or plant type Shrub
  • Native locale Non-native
  • Size range Large shrub (more than 8 feet)
  • Light exposure Full sun (6 hrs direct light daily), Partial sun / shade (4-6 hrs light daily)
  • Hardiness zones Zone 4, Zone 5 (Chicago), Zone 6, Zone 7, Zone 8
  • Soil preference Acid soil, Alkaline soil, Moist, Sandy soil, well-drained soil
  • Tolerances Alkaline soil, Clay soil, Road salt
  • Season of interest mid spring, early fall
  • Flower color and fragrance White
  • Shape or form Open, Oval, Upright
  • Growth rate Moderate

Native geographic location and habitat:

Blackthorn is native to Europe, Scandinavia, Siberia and Iran.

Attracts birds or pollinators:

Its fleshy fruit attracts songbirds and game birds.

Bark color and texture:

The branches of blackthorn are stiff, blackish-brown, and spiny.

Leaf or needle arrangement, size, shape, and texture:

The Blackthorn’s leaves are alternate. They are an elliptical to oval shape, 11/2 to 2 inches long with a pointed tip and serrated leaf margins. Blackthorn’s leaves are dark green and change to yellow in the fall.

Flower arrangement, shape, and size:

In the early spring, Blackthorn’s have five-petaled, creamy-white flowers in small clusters before leaves emerge. Their flowers are insect pollinated.

Fruit, cone, nut, and seed descriptions:

The fruit is a black berry with a purple-blue waxy bloom, ripening in autumn. The berries are tart and astringent, often used in jams and for medicinal purposes.

Plant care:

Blackthorn is a stiff, shrubby plant found in sunny hedgerows and edges of the woods. It is often confused with plum cherry (Prunus cerasifera). Blackthorn can grow 9 to 12 feet high and 12 feet wide. Sometimes reaching a more tree-like size at about 16 feet high. It prefers well-drained, slightly acidic to neutral soil pH in full sun to light shade.

List of pests and diseases:

Blackthorn can get cankers, leaf spots and borers. They are salt tolerant.

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