Sandy’s Garden ... Iberis Semperflorens

Sandy Simpson
Sandy Simpson

I was idly browsing … and admiring, I might add … the variety and quality of the plants on offer in one of the local independent garden centres when pots of Iberis semperflorens caught my eye.

There was no common name offered for these plants which were absolutely covered in dainty, white flowers, each about 1½ inches across … say, 4 cm in today’s terms. Eye-catchingly attractive, I determined to find out more and was genuinely surprised at how difficult this turned out to be. Starting with a visit to the Royal Horticultural Society’s (RHS) website, I learned that Iberis semperflorens is commonly (?) known as broad-leaved candytuft, is a member of the cabbage family … the Brassicaceae … and is listed in the RHS Plant Finder, where I read, “At present our information about this plant is limited to a list of the nurseries that supply it. In time we will be adding more details including a description, growing information, advice and photographs.”

Hmmm, this is perhaps not terribly helpful. Still, pressing on, I read that one of the nurseries which supplies Iberis semperflorens is Pershore College … part of the Warwickshire College Group … which is an RHS regional centre with courses, lectures and workshops on offer. Now it so happened that we have friends who live in a genuine chocolate-box thatched cottage in Bredons Norton, a hamlet just 6½ short miles from Pershore. They live on the lower slopes of the Bredon Hills, the self-same hills of which Pershore College boasts, “Our halls of residence have fantastic views of the Bredon and Malvern Hills.” And, having enjoyed staying in a sixteenth-century house very close to Pershore, I know that the climate there is a tad gentler than that with which we are blessed in central Scotland. But I still haven’t found out much about Iberis semperflorens.

Then I found an academic website which yielded this information in an abstract from a scientific study into ‘Propagation Techniques for Iberis Semperflorens’ by Giovanni Iapichino and Massimo Bertolino, published by the International Society for Horticultural Science. “Recently, many plants native to the Mediterranean region are sought and selected for their ornamental value. Iberis semperflorens is an evergreen subshrub (30-60 cm) endemic to southern Italy and Sicily with attracting white fragrant flowers in corymbs which flowers from October to April. Although Iberis semperflorens has potential for pot cultivation and outdoor ornamental use there is a lack of detailed and published research results on the propagation of this winter flowering species.”

We’re getting there! Now we know that Iberis semperflorens … ‘the constant-flowering (semperflorens) plant from the Iberian Peninsula’ … is a small, spreading, evergreen shrub, covered in attractive white flowers in the depths of winter into spring; I can add, from personal observation, that it has narrow, dark green leaves; and I further learn, from an American gardening website, that it prefers growing in full sun, that it does best in moist, but well-drained soil, that it doesn’t like acid soil and that it is best suited for growing in containers or, since it reaches a maximum height of some 20 cm … say, 8 inches in old money … in the front of a border. Despite being named Iberis semperflorens … ‘the constant-flowering (semperflorens) plant from the Iberian Peninsula’ … it hails originally from the sea cliffs of western Italy and Sicily, rather than from the south-west corner of Spain and Portugal. Given its preference for the Mediterranean climate, it is hardly surprising to learn that it is not fully hardy. So, since I don’t have a suitable greenhouse, I reluctantly left these attractive little shrubs on the garden centre’s benches for someone else to enjoy.