Blackberry

Family

Rosaceae

Habit

Shrub

Height

3 m

Spread

3 m

Growth

very fast

Lifespan

30 years

First yield

after 2 years

Full yield

after 3 years

Productive years

6–25 years

Hardiness

zone 5–9

Shade tolerance

full shade

Soil

Sand, Silt, Loam

Soil moisture

very dry – very wet

pH

4.5 – 8

Synonyms

Brombeeren

Times apply to the northern hemisphere in a temperate climate and shift with altitude and cultivar.

Edible: The glossy black aggregate fruits consist of twenty to fifty drupelets and ripen from August into October, with good cultivars carrying on into November. Unlike the raspberry, the fruit does not come away from the conical receptacle when picked — it stays inside the berry as a pale plug and is the surest way to tell the two apart. Fully ripe, blackberries are very juicy and aromatic; picked unripe they are not only sour but also sit heavily on some people's stomachs. Besides fresh eating they yield juice, must, wine, liqueur, compote, preserve, jelly and fruit leather. Dried leaves, preferably young ones, are a classic ingredient of herbal tea blends. The fruit is not the only edible part: the young shoots of March and April, stripped of their prickly midrib, taste mildly tart raw and can be steamed like spinach.

Medicinal: Dried bramble leaves are a traditional ingredient of herbal tea blends, credited with an anti-inflammatory effect and drunk by tradition for fever and complaints of the respiratory tract. The fruit was said to strengthen the stomach and build the blood, and occasionally to ease rheumatism. All of these are handed-down uses without proven efficacy.

Other uses: A violet to dull blue dye can be obtained from the fruit; it was once used to deepen the colour of red wine. Stripped of thorns and bark, the tough canes make usable weaving and binding material for baskets and twine. The species has its greatest effect, though, at the stand level: as a pioneer it covers clear-fells, burnt ground and abandoned land, and its far-reaching root system binds banks and protects them from erosion. In hedgerows and field hedges it forms opaque, virtually impassable barriers that give small mammals and birds cover — and shield young trees from browsing so effectively that whole generations of woody plants come up under the thorns.

Blackberries are undemanding: moderately fertile, free-draining soil from calcareous to slightly acid will do, while waterlogging and salty sites are avoided. Sun gives the sweetest fruit; in half shade it ripens later and more sparsely. The weak point is frost hardiness — because many types are winter- to semi-evergreen they count as only moderately hardy and repay a mild, sheltered position, with winter protection worthwhile in harsh areas. In commercial growing the canes are trained on a wire frame with three or four wires, upright cultivars as a fan and trailing ones horizontally; spacing is 1.5 to 4 m depending on cultivar, with 2.5 to 3 m between rows. Pruning follows the two-year rhythm: spent canes are cut out at the base after harvest and the new season's canes tied in.

Blackberries are most easily propagated vegetatively, and the long canes do much of the work themselves: bend a cane tip down in summer and cover it with soil, and it will root within a few weeks and can be severed in autumn as a plant in its own right. Layering whole shoots and lifting rooted suckers work just as reliably. Softwood cuttings in summer and root cuttings in winter are further options. Seed is possible but matters only in breeding: it is collected before full ripeness and stratified. Since most microspecies reproduce asexually and the garden cultivars are hybrids, seedlings do not come true anyway.

The bramble is among the most valuable of all wild shrubs. Its long, staggered flowering has yielded records of 53 wild bee species, along with hoverflies, beetles and butterflies in numbers; because the bloom stretches over weeks, it is a dependable summer forage. It serves as a larval food plant for 21 moth and butterfly species, four of them specialists. The fruit is used by 32 bird species and by many mammals, from dormice to foxes. Its real asset, though, is structure: impenetrable thorny thickets provide breeding habitat for shrikes, warblers and dunnocks and give hedgehogs and small mammals cover from predators.

Special features: Drought-resistant; It rapidly spreads across vast and disrupted areas with tendrils that can grow up to a meter long, which then re-root and produce runners; Shields young trees from wildlife harm; The shoots perish after fruiting, while the roots have a lifespan of more than 100 years; Numerous varieties and popular species exist, some without thorns.

Europe to the Mediterranean and Macaronesia. The name covers not a single species but an aggregate of several hundred closely related microspecies which reproduce largely asexually and can therefore hardly be told apart cleanly. The group occupies large parts of the northern hemisphere into arctic latitudes and also occurs in tropical mountains. In central Europe the wild blackberry is native and ranges from the lowlands up to around 1,700 m. At least sixteen different Rubus species have gone into the garden cultivars, which is why botanists no longer list them as Rubus fruticosus but as Rubus sect. Rubus.

The blackberry is a plant of transitions. It colonises clear-fells, woodland edges, scrub margins, open woodland and scree slopes — anywhere a site has been disturbed and closed woodland has not yet returned. Moderately fertile soil is enough for it, and anything from calcareous to slightly acid suits it; only salt it tolerates poorly. It does best on fresh to dry ground in sun or half shade. In that role it acts as a pioneer: its thorny tangles keep browsing animals away from young tree seedlings, so that the next generation of woodland can grow up under its protection.