The genus Rubus, (especially the blackberries, which are often loosely referred to as Rubus fruticosus agg.) presents some of the most difficult taxonomic problems. This is partly due to the frequency of polyploidy; also to the frequent occurrence of hybridization; and also due to apomixis, where minor differences between plants are preserved because seedlings are genetically identical to their parent. As a result, differences of opinion on the number of species to be recognized from a given region can vary tremendously (for example, a treatment by M. L. Fernald[] in 1950 recognized 205 species for the northern half of the eastern United States plus parts of southeastern Canada, whilst H. A. Gleason and A. Cronquist in 1991 recognized only 25)[]. Where possible, a relatively conservative approach is taken here[].

Common Name: Dewberry

General Information

Rubus caesius is a deciduous shrub producing each year a cluster of arching, prickly, biennial stems from a woody rootstock. Growing 50 - 150cm tall, the stems only produce leaves, and do not flower, in their first year, forming flowering branches in their second year and then dying after fruiting. When the tips of one-year stems touch the ground they produce roots and develop into new plants, thus forming a thicket of growth[].
The plant is harvested from the wild for local use as a food. It is sometimes cultivated for its fruit, especially in the Caucasus[], and has been used in plant breeding programmes to instill greater frost tolerance..

Known Hazards

None known

Botanical References

, , ,

Range

Eurasia - Norway south to Portugal, east through Russia to western Siberia. central Asiia western China, through Turkey to Lebanon and Afghanistan

Habitat

Hedgerows, amongst shrubs and in rough dry meadowland, usually on basic soils[, ]. Forests, ravines, among shrubs, clearings, banks of rivers and streams, forest and inundated meadows, gardens, orchards, roadsides, hedges[].

Properties

Edibility Rating
Other Uses Rating
Habit	Deciduous Shrub
Height	1.00 m
Pollinators	Bees, Flies, Beetles, apomictic
Self-fertile	Yes
Cultivation Status	Cultivated, Wild

Cultivation Details

Easily grown in a good well-drained loamy soil in sun or semi-shade[, , ]. Succeeds on chalky soils[].
Rubus caesius hybridizes with the true blackberries, and in that way numerous minor species have arisen of intermediate character. One of the most interesting is Rubus balfourianus Bab., which probably arose originally from a cross between Rubus caesius and Ruus gratus. Not only are the pink or white flowers sometimes as much as 5cm wide, but they are borne throughout the summer and early autumn, and the fruits, though often abortive, are sometimes large, with a mulberry flavour[]
Plants in this genus are notably susceptible to honey fungus[].

Edible Uses

Fruit - raw or cooked[, , , , ]. Succulent but not very tasty[]. Insipid[]. An agreeably acid flavour, it is considered to be superior to ordinary blackberries though the fruit is rather small and consists of just a few drupes[]. The fruit can be used for making jellies, preserves etc[].

The young leaves are a substitute for tea[]. The fresh or dried leaves are used as a tea substitute[, , , ].

Medicinal

None known

Agroforestry Uses:

Most, if not all, thicket-forming species of Rubus have good erosion control value. They usually grow satisfactorily on barren and infertile soils and invade and occupy eroded areas. They also establish quickly on burns, old fields, and logged areas. Forming extensive and nearly impenetrable thickets, they can provide excellent cover for wildlife as well as nesting sites for small birds. They are often natural pioneer species, paving the way for woodlands to develop, but they should only really be used within their native range in order to avoid any risks of them invading other habitats[, ].

Other Uses

This species has been of interest to plant breeders in the USA since 1919, being valued for its tolerance to frost. It participated in the establishment of the cultivar 'Fertödi Bötermö'[].

A purple to dull blue dye is obtained from the fruit[].

Propagation

Seed - requires stratification and is best sown in early autumn in a cold frame. Stored seed requires one month stratification at about 3°c and is best sown as early as possible in the year. Prick out the seedlings when they are large enough to handle and grow on in a cold frame. Plant them out into their permanent positions in late spring of the following year.
Cuttings of half-ripe wood, mid summer in a frame[].
Tip layering in July. Plant out in autumn.
Division in early spring or just before leaf-fall in the autumn[].