Black hawthorn (Crataegus douglasii) is a shrub species that is used for ornamental purposes and as a food source for livestock and wildlife. Livestock often graze on the foliage of this plant, while wild bird species eat the berries.
I. Appearance and Characteristics
Crataegus douglasii is a North American species of hawthorn known by the common names black hawthorn and Douglas’ thornapple.
The species is named after David Douglas, who collected seed from the plant during his botanical explorations.
Formerly placed within the species, Crataegus douglasii var. duchesnensis is now considered to be a synonym of Crataegus saligna.
The thorny shrub is native to northern and western North America, where it grows in varied habitats from forest to scrubland. It is most abundant in the Pacific Northwest.
Crataegus douglasii is a compact erect bushy shrub growing to 8–9 metres (26–30 feet) tall with a trunk of up to 10 centimetres (4 inches) thick. It is covered in fan-shaped green leaves about 2.5–5 cm (1–2 in) long with teeth along the distal margin. Thorns along the branches are 1–2.5 cm long.
White flowers with greenish centers grow in bunches at the ends of each thin branch. The fruit is a blackish pome up to about 1 cm across, containing 3–5 rocklike seeds.
The foliage is browsed by cattle and sheep. Various birds, including quail, the Hungarian partridge, and ring-necked pheasant feed on the berries, as do bears and other animals. Magpies nest in the branches. The species is a larval host to the gray hairstreak, mourning cloak, pale tiger swallowtail, and western tiger swallowtail.
II. How to Grow and Care
Black hawthorn is a hardy and resilient species, well-suited to a variety of conditions, indicating an easy care difficulty level. Key care needs include full sun to partial shade and well-drained soil, with moderate tolerance for drought once established. Special care points focus on pruning to maintain desired shape and size, and monitoring for pests such as aphids and scale insects, which can be occasionally problematic.
Sunlight and Soil
A full sun lover, this tree is easily grown in moist to wet soils. It tolerates part shade but best fruit production occurs in full sun.
Watering
Black hawthorn thrives in environments that mimic its native moist habitats, exhibiting a preference for consistent moisture. It has adapted to tolerate brief periods of dryness, but generally maintains a balance with moderate water needs. For optimal health, black hawthorn should be watered once every 1-2 weeks. Given its affinity for moisture, black hawthorn is more commonly grown outdoors where it can benefit from natural rainfall patterns. This deciduous plant’s water uptake is closely tied to its growth cycle, peaking during the active growing season.
Fertilizing
For optimal growth, black hawthorn thrives with balanced nutrition fertilizers. Annually, apply a slow-release formula at the onset of spring to bolster flowering and fruiting, maintaining plant vigor. Use recommended dose on the label, avoiding overfertilization which can harm black hawthorn. Adjust fertilizing practices based on black hawthorn’s life cycle and seasonal needs. Applying compost can improve soil fertility, benefiting black hawthorn long-term. Remember, always water black hawthorn after fertilizing to aid nutrient absorption and prevent root burn.
Pruning
Requires only minimal pruning in late winter or early spring, to remove damaged, diseased, or misplaced growth.
Propagation
Black hawthorn propagates best through cutting and layering in autumn and winter. Propagation is moderately challenging, with success indicated by new leaf growth. Ensure adequate moisture and warmth for optimal results.
Transplanting
The ideal time to transplant black hawthorn is during the dormancy period, typically late fall to early spring (S3-S4). This is when the plant’s energy is focused underground, minimizing shock. Ensure a sunny or partly shaded location and maintain regular watering post-transplant. Your black hawthorn will thrive with these considerations.
Repotting
For black hawthorn, a mid-sized, bushy species, repot every 2-3 years to accommodate growth. Early spring is optimal to align with its active growth phase. Choose a container slightly larger than the root ball to ensure space for expansion without oversizing, which can lead to waterlogging. After repotting, maintain consistent watering to aid recovery, but avoid overwatering. Use well-draining soil and place in a location with full sun to partial shade for best results.
Pests and Diseases
Keep an eye out for cedar-hawthorn rust, cedar-quince rust, fire blight, fungal leaf spots, powdery mildew, cankers, apple scab, borers, caterpillars, lace bugs, leafminers, and scale.
III. Uses and Benefits
- Ornamental uses
Black hawthorn is a small tree or a shrub with white spring flowers attractive to pollinators and showy red berries that persist in the canopy for a long time. It can be an ideal specimen tree in native gardens, or useful as a lawn or street tree. In brush form, it can be used within hedges or barriers.
- Culinary uses
The fruits were a good food source for Native American peoples such as the Cheyenne and Nlaka’pamux.
