This species is closely related to Rubus occidentalis[].
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: Mora De Castilla

General Information

Rubus glaucus is a deciduous climbing shrub producing each year a cluster of erect or arching, biennial stems from a woody rootstock; the stems can be around 3 metres long. It scrambles into other plants, supporting itself by means of its prickly stems. The stems only produce leaves, and do not flower, in their first year of growth; forming flowering branches in their second year and then dying after fruiting
The plant produces a fruit of excellent quality that is highly esteemed within its native range[, , ]. It is often cultivated in S. America for this fruit and sold in local markets[, , ].

Known Hazards

None known

Botanical References

,

Range

S. America - northern Andes through Central America to Mexico.

Habitat

Moist or wet thickets or open fields, at elevations from 1,200 - 3,000 metres in Guatemala[].

Properties

Edibility Rating
Other Uses Rating
Habit	Deciduous Shrub
Height	3.00 m
Pollinators	Apomictic
Self-fertile	Yes
Cultivation Status	Cultivated, Wild

Cultivation Details

Plants can be grown in warm temperate to subtropical climates, and at higher elevations in the tropics in regions with a well-distributed, medium rainfall[]. They can tolerate occasional, short-lived temperatures down to between -5 and -10°c[].
Easily grown in a good well-drained loamy soil in sun or semi-shade[, , ].
Seedlings can commence fruiting when 2 years old[].
Yields of up to 20 tonnes of fruit per hectare are achieved in S. America[].
Plants in this genus are notably susceptible to honey fungus[].

Edible Uses

Fruit - raw or cooked[, ]. Rich, tart and very juicy, they are superior in flavour and quality to most cultivated blackberries and raspberries[]. Some varieties have a very delicate flavour[]. One of the best fruits of the whole earth[]. The fruit is up to 3cm long[].

Medicinal

None known

Other Uses

Because the plant has a resistance to cane-spot disease (Mycosphaerella rubi) and also has potential for improving the quality of fruits, this species is crossed with Rubus cultivars in breeding programmes[].
This species could be useful in hybridization programmes with American and European blackberries and raspberries, but it is susceptible to some N. American raspberry diseases[].

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[].