This beautiful deciduous barberry was raised in the Royal Horticultural Society's garden at Wisley and was first exhibited on 7th November 1916 at the Horticultural Hall, Westminster, when it was awarded a First Class Certificate. It was raised from seed of B. wilsoniae, the result of hybridisation by insect agency with some other species, possibly B. aggregata. In foliage it bears considerable resemblance to B. wilsoniae, the leaves being oblanceolate, but they are, on the average, larger. Its remarkable beauty is in its fruits, which are borne two to four on a main-stalk 3⁄4 in. long and hang from the branches in great profusion. Each berry is about 5⁄8 in. long, oblong-ovoid, and of a beautiful translucent coral-red.
Two excellent fruiting shrubs of the same type are 'Crawleyensis', raised by Messrs Cheal, with remarkably large fruits, and 'Cherry Ripe', a seedling from it raised by Mrs Ahrendt of Stonefield, Watlington, Oxon., with almost round berries which are creamy white when young, becoming cherry-red. For other deciduous hybrids see B. × carminea.
B. suberecta Ahrendt – A species of rather doubtful standing, raised by the late Harry White of Sunningdale Nurseries from seeds sent to him by the late J. C. Williams of Caerhays as “B. dictyophylla from the Tali Range” and said to have been collected by George Forrest in the period 1917-19. The plants were originally distributed as “the upright form of B. rubrostilla” and resemble that hybrid. Another species described from this batch of seed is B. ambigua Ahrendt.
From the Supplement (Vol. V)
It should be added to the description that the flowers of this berberis are large – about 5⁄8 in. across.
The statement that the original plant was raised from seed of B. wilsoniae requires qualification. Mr Chittenden, who described it in 1917, later told Dr Ahrendt that the seed-parent came from Veitch's Coombe Wood nursery under the label B. wilsoniae, but that it differed somewhat from the other plants in the batch and might, he thought, have been a seedling raised at Coombe Wood from a plant of the true B. wilsoniae. As to 'Rubrostilla', it is not impossible that B. angulosa or one of its allies such as B. concinna might have been the pollen-parent. In view of its obscure parentage, 'Rubrostilla' does not merit botanical recognition as B. × rubrostilla. Still less would it be appropriate to place under this collective name the clones mentioned under B. × carminea, which have a quite different type of inflorescence.
'Rubrostilla' is still available in commerce.