Tufty clubland
I sempervirens is a godsend for gardeners who want their rockeries to shine, writes David Overend.
People tend to take a lot for granted; we assume that plants will keep on doing what they always do – growing and flowering, growing and fruiting, growing etc... So it can come as a shock when a plant fails to put in an appearance at the allotted time.
Thankfully, such shocks are few and far between and spring brings with it snowdrops, daffodils, apple blossom, a worrying number of weeds – and the delightful but vastly under-rated Iberis commutate, AKA perennial candytuft, and also called I sempervirens.
For something so small, it can provide a lot of pleasure; in fact, this member of the cabbage family (Brassicaceae) has the ability to begin flowering in April and still be blooming well into June.
Iberis can be annuals, evergreen perennials or even shrubs, with narrow leaves and racemes of white, pink or purple flowers, but it is the rockery form which has proved to be such a godsend to gardeners.
I sempervirens is a spreading evergreen which may reach 30cm in height but it tends to spread outwards rather than upwards, so it’s best to keep a eye on it if you plant it in a small rockery where its narrow, dark green leaves will gradually overpower many a more genteel plant.
The flowers tend to be pure white, and start out almost flat before gradually fattening out on top of short stems. If it gets out of control, pull it up; otherwise, prune it lightly after the flowers have faded.
This is a little plant which loves the sun, so give it an open site, a south-facing wall where it can root in cracks and crevices, or even encourage it to take hold in gravel paths.
It likes moisture but not waterlogging, can tolerate most soils (in fact, poorer soils seem to suit it down to the ground) and is just as much at home in a container as it is in open ground.
Don’t confuse it with Arabis (also known as rock cress), another pretty, small, whiteflowering plant that helps brighten late winter and early spring. The blooms can start to appear as early as December and continue till the following April, so this is the perfect plant for a rockery or scree garden.