Plant Profile: Epimedium (Barrenwort)

Long-lived perennials with slowly creeping rhizomes, epimediums combine visual charm with remarkable resilience and ruggedness.

In the Berberidaceae family, the genus Epimedium contains around 50 species extending from Japan and China through the Caucasus into the western Mediterranean. While the East Asian epimediums tend to be larger flowered, and are renowned for their delicate beauty, it is the species from the western part of the range, notably E. perralderianum (Algeria) and E. pinnatum (Turkey) and their hybrids, that are best suited to urban conditions.

Like many stress-tolerant plants, these species have evolved to survive in challenging environments by conserving resources in tough, long-lasting organs—rhizomes and leathery leaves.

Among the most reliable performers for city use are the cultivars E. x perralchicum ‘Fr?hnleiten’, with deep yellow flowers, and the paler yellow E. x versicolor ‘Suphureum’, both of which are able to handle a variety of testing conditions, including dry shade and building rain-shadows.

The dainty flowers (aptly known as Elfenblumen in German) emerge simultaneously with the fresh leaves, which are initially soft in texture with fine prickles on the margins and conspicuous marbled veining in a mixture of bronze-red and matt green. The foliage becomes glossy green and leathery as it matures and is retained through the winter, often in an evergreen state.

If plants need neatening, old leaves can be cut back in spring (ideally before the flowering stems begin to elongate), but epimediums are capable of remaining attractive and structurally effective with almost no maintenance — a valuable characteristic.

The rhizomes form a dense mat that makes a practically weedproof groundcover. Relatively shallow-rooted epimediums coexist with tree roots in their natural habitat, so they can be tactically valuable to the designer by facilitating high-quality foliage cover on congested sites where soil depth is restricted by infrastructure (e.g. pipes) close to the surface.

By Martin Deasy, a UK-based horticulturist and landscape designer. Originally published in the July-August 2024 edition of FloraCulture International .