Chapters
Rubus - Care Guide
Introduction to Rubus
Ornamental bramble
Rubus come in many shapes and sizes, some with fruits – some without, some with serious prickles – some without, some with a shrubby upright habit and some as groundcover plants, some as evergreens and some are deciduous. Some species need serious pruning, and some are best left well alone.
The plants which we offer are not common blackberries or brambles; Rubus fruiticosus, or raspberries; Rubus idaeus. Ornamental brambles are cultivated for their flowers, foliage, or attractive winter shoots but few produce real quantities of edible fruits either as blackberries or raspberries. Many are interesting plants for the shrub border or for growing as freestanding plants in a woodland context. Others make seriously good and vigorous groundcover which can take over steep banks or hedges in a carpet and prevent almost all other weeds from getting a look in.
With all this in mind it is necessary to introduce a few categories of our own to help make your choice of which plant to grow rather easier.
Evergreen groundcover Rubus
R. tricolor, the Korean raspberry, does have yellowish-red raspberries which are very satisfactory with your cornflakes in August or September. As an evergreen, creeping shrub, it takes quite some beating as groundcover. When lots of plants are grown together on a stony bank the creeping and arching shoots, which are covered in red bristles (not prickles), can form a dense mound 2-3ft tall. A 20ft bare bank can be covered in no time at all and the white flowers in summer are attractive too.
R. tricolor ‘Betty Ashburner’ is identical except that it has a different sort of heart shaped green leaves which have wavy margins. You may find that plants revert to R. tricolor in large banks, but the mix of leaf forms has its own attractions.
Rubus with no prickles – or very few!
R. ‘Beneden’ is a spreading deciduous shrub with arching, thornless, branches growing eventually to about 10ft with a smaller spread. It has attractive peeling bark and rose-like saucer-shaped solitary white flowers in late spring and summer.
R. spectabilis ‘Olympic Double’ grows to 6-8ft in maturity and is thicket forming with many shoots in the clump. The flowers in April to May are very showy indeed and double purple-pink. We do not usually bother to thin the thicket here as one would if growing fruiting raspberries. The new shoots are slightly prickly, but the mature canes or shoots are not.
R. odoratus, the flowering raspberry, is a deciduous shrub growing to 8ft or so with a similar spread. It has large five lobed leaves and the shoots are spineless. From summer through to autumn it has panicles of cup shaped pale pink flowers. The ensuing flattened red fruits are tasteless. We grow this plant in shade which it seems to enjoy.
R. lineatus is a semi-evergreen shrub with us which grows with us to 4-5ft with many shoots from the base. The leaves are quite unique and very beautiful. They have five leaflets which are dark green on their topsides and the undersides are completely covered with a shining, silvery down. The leaves are conspicuously veined. Our stock plant has virtually no prickles and enjoys a warm sheltered position. Once it was mature our plant produces just a few yellow raspberries which only ripen late in the year.
R. henryi is a rare species which also has interesting leaves and grows to about 15ft. It flowers (white) in early to mid-summer with edible fruits in the following months. Rabbits have seemed to like this species so a wire netting surround initially may help.
Prickly bramble-like or raspberry-like Rubus species
R. calophyllus grows as a shrub to around 3ft in height with minutely prickly arching stems. The long leaves are silky-hairy underneath with prickles on the midrib. The flowers are a striking claret red and this is followed by rather insipid orange or red fruit. This Rubus needs protection from cold winds.
R. cockburnianus is a thicket forming deciduous shrub producing arching shoots which are covered in a brilliant white indumentum in winter. For this reason, and despite the fierce prickles, it is best to thin the thicket to have just a few stems to admire in the winter sun perhaps alongside winter flowering heathers or stemmed dogwoods. It has terminal racemes of saucer-shaped purple flowers and the leaves are pinnate with many lance shaped leaflets that have white hair below. It will grow to about 8ft with a similar spread and is extremely tough and hardy.
R. cockburnianus ‘Golden Vale’ is a form with striking yellow young leaves which then turn lime-yellow.
R. phoenicolasus, the Japanese wineberry, has bristly, reddish, arching stems and trifoliate leaves which are white felted underneath. It flowers in July in terminal bristly clusters of small pale pink flowers. The fruits, unlike many other Rubus species, are very edible and bright orange-red but you will be in a race with the birds to see who gets there first.
R. rosifolius ‘Coronarius’ is a less prickly bramble with very large creamy white flushed green flowers. Unusually, a second flower may well appear from the centre of the first after the first has fallen. This is a form grown for its flowers. There are no fruits on this variety.
R. thibetanus is an erect, clump forming deciduous shrub with prickly stems which are, like R. cockburnianus, white bloomed in winter. The leaves and leaflets are grey-hairy above and white-hairy below. Red-purple flowers in summer appear singly or in terminal racemes followed by black fruit. The pruning treatment to expose the white stems is as you would expect with very thick gloves!
Climbing Rubus species
The rare R. ichangensis is a wall shrub or one you can allow its new shoots to romp up through a nearby evergreen. Our stock plant has a lot of purple-red blotching on its older leaves which can be attractive. It easily covers a 12ft high wall and, after initially needing to be tied in, it now grows through several neighbouring plants. The flowers are in foot long terminal and branched clusters. The flowers are quite small and white and, in late September or October, some of the panicle develops small red raspberry-like fruits which are delicious even in small quantities. After a dry summer you get more fruit than after a wet one. The prickles are largely insignificant but can catch you out!
We hope soon to stock R. squarrosus with especially unpleasant tiny spines on each white felted branch.
Ground cover on steep bank - Video Tip
Plants
