Lamium galeobdolon
yellow archangel
Overview
Lamium galeobdolon is a low, spreading perennial in the mint family, forming a mat 8-24 inches (20-60 cm) tall that broadens steadily by rooting stolons. The square stems carry paired, coarsely toothed leaves 1.5-3 inches (4-7.5 cm) long, often marked with silver between the veins. The foliage is semi-evergreen, persisting through mild winters and dying back in colder ones. In late spring whorls of hooded, two-lipped yellow flowers 0.6-0.8 inch (1.5-2 cm) long form in the leaf axils along upright shoots. Bumblebees and other long-tongued bees work the flowers for nectar. After bloom the trailing stems root at the nodes and run outward, allowing the plant to cover ground quickly in shade. It grows in full to part shade and tolerates dry soil once established, traits that lead to its frequent use on difficult shaded banks. The same vigor has made it invasive in the Pacific Northwest and parts of Europe outside its range, where it overruns woodland floors and crowds out native plants. Several silver-leaved selections are grown in gardens for their patterned foliage.
Native Range
Lamium galeobdolon is native to Europe and western Asia, from the British Isles and Scandinavia south to the Mediterranean and east into the Caucasus and Iran. It grows naturally in deciduous woodland and shaded hedgerows.Suggested Uses
Grown as a shade groundcover under trees and shrubs, on shaded slopes, and in containers and hanging baskets where the trailing stems spill over the rim. It is spaced 12-18 inches (30-45 cm) apart and fills in within a season or two. In regions where it has naturalized it is confined to containers or bounded beds to prevent escape into wild areas.How to Identify
Appearance
Size & Dimensions
Height8" - 2'
Width/Spread2' - 3'
Bloom Information
Flowering occurs in mid to late spring, mainly April through June, on upright shoots rising above the creeping mat. The whorled yellow flowers open over three to four weeks. Scattered later flowers can appear in cool, moist summers.
Detailed Descriptions
Foliage Description
green with silver markingsGrowing Conditions
Sun Requirements
Requires 2-6 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 in part to full shade on moist, well-drained soil enriched with organic matter. Established plants tolerate dry shade and root competition under trees, conditions where many groundcovers thin out. Full sun and dry exposed sites scorch the foliage. The stolons root as they spread, so the plant fills bare ground within a season or two and can move beyond its intended area. Cutting back after bloom keeps the mat dense and tidy. Because it spreads readily, it is kept clear of woodland edges and natural areas in regions where it has escaped.Pruning
The planting is sheared or mown after flowering to remove faded shoots and tighten growth. Trailing runners that stray past the intended edge are cut or pulled through the season to check spread. Plants that brown in hard winters are cut back in early spring as new growth begins.Container Growing
✓ Suitable for container growing
Minimum container size: 1 gallons