Epimedium × rubrum
red barrenwort
Garden hybrid; parents from Europe and East Asia
Overview
Epimedium x rubrum is a clump-forming, semi-evergreen perennial growing 8–12 inches (20–30 cm) tall and 12–18 inches (30–45 cm) wide, spreading slowly by rhizomes into a low ground cover. It is a hybrid of E. alpinum and E. grandiflorum. The compound leaves are divided into heart-shaped leaflets 1.5–3 inches (4–8 cm) long, edged with small spines; they emerge reddish-bronze in spring, turn mid-green in summer, and flush red again in autumn. In mid to late spring, wiry stems carry sprays of small spurred flowers about 0.75 inch (2 cm) across, with crimson-red outer sepals and pale yellow inner petals. The plant grows in woodland conditions and tolerates dry shade and root competition once established, though it spreads slowly and the old foliage looks tatty by late winter. Hardiness covers USDA zones 4–8. Cutting the old leaves away in late winter reveals the spring flowers and fresh growth. It is grown as ground cover under trees and shrubs, at the front of shaded borders, and in woodland gardens.
Native Range
Epimedium x rubrum is a garden hybrid raised in cultivation, not a wild plant. Its parent species, E. alpinum from southern Europe and E. grandiflorum from East Asia, grow in woodland and on shaded slopes.Suggested Uses
Epimedium x rubrum is grown as ground cover in dry and moist shade, under trees and shrubs, and at the front of shaded borders and woodland gardens. The spring flowers and changing leaf colour give two seasons of interest. It also works between larger shade perennials such as hostas and ferns.How to Identify
Appearance
Size & Dimensions
Height8" - 1'
Width/Spread1' - 1'6"
Bloom Information
Flowering occurs in mid to late spring, usually April to May in the Northern Hemisphere, when sprays of crimson-and-yellow spurred flowers rise on wiry stems for about 3–4 weeks. The flowers are seen clearly when the old leaves are cut away beforehand. Bloom coincides with the reddish flush of new foliage. Little fruit follows the flowers.
Detailed Descriptions
Flower Description
Crimson-red and pale yellowFoliage Description
Reddish-bronze in spring, mid-green in summer, red in autumnGrowing Conditions
Sun Requirements
Tolerates up to 4 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Grow Epimedium x rubrum in partial to full shade in moist, humus-rich, well-drained soil, though it tolerates dry shade and root competition once established. Water during the first season and in prolonged drought; established clumps are markedly tough. A spring mulch of leaf mould conserves moisture and feeds the crown. Cutting away the old, weathered leaves in late winter before flowering keeps the planting fresh and opens up the flowers to view. The plant spreads slowly and needs little other care. It is largely free of pests and disease, though vine weevil can affect plants in containers.Pruning
Epimedium x rubrum needs no conventional pruning. The previous year's tatty leaves are sheared off in late winter, before the flower stems and new foliage emerge. Clumps are lifted and divided in spring or early autumn to propagate or rejuvenate them.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
winter
Container Growing
✓ Suitable for container growing
Minimum container size: 2 gallons