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Lamium orvala
balm-leaved archangel
Southeastern Europe (Italy, Austria, Slovenia, Balkans); mountain woodland margins and shaded rocky slopes
Overview
Lamium orvala is a clump-forming, herbaceous deciduous perennial reaching 18–24 inches (45–60 cm) tall and 18–24 inches (45–60 cm) wide. The species forms a single discrete clump that expands only from the crown; it does not run by stolons or rooting stems, separating it from the groundcover-scale Lamium maculatum and Lamium galeobdolon, which extend outward 12–24 inches (30–60 cm) per season. Hooded, two-lipped flowers are 1–1.5 inches (2.5–4 cm) long in dusky pink to mauve-purple and open in dense whorls at the upper leaf axils from April through May; individual flower length is about twice that of the 0.5–0.75 inch (1.3–1.9 cm) flowers of L. maculatum. Broadly ovate, toothed, medium green leaves are 3–5 inches (8–13 cm) long and arranged in opposite pairs on square stems. Foliage is plain green without the central silver markings of L. maculatum. Growth rate is moderate. Hardy in USDA zones 5–8. Prolonged summer drought can trigger partial summer dormancy with loss of foliage, the species is not a spreading groundcover and will not knit together into a continuous mat, and the plain green leaves do not contribute the silver-leaf element that patterned Lamium spp. species bring to shade plantings.
Native Range
Lamium orvala is native to southeastern Europe, including Italy, Austria, Slovenia, and the Balkans, on mountain woodland margins and shaded rocky slopes.Suggested Uses
Planted in shaded borders, woodland gardens, and positions under deciduous trees at 18–24 inch (45–60 cm) spacing, and in containers of 3 gallons (11 L) or larger. The clumping, non-running habit suits mixed-perennial shade plantings where spreading deadnettles would overrun slower-growing neighbors. The larger flowers produce more visual impact than L. maculatum at close range. The plain green leaves do not provide the silver-leaf element of patterned Lamium spp. species, and the species is not suited to continuous-mat groundcover use, full sun, or dry exposed sites.How to Identify
Appearance
Size & Dimensions
Height1'6" - 2'
Width/Spread1'6" - 2'
Reaches mature size in approximately 2 years
Bloom Information
Produces hooded, two-lipped flowers 1–1.5 inches (2.5–4 cm) long in dusky pink to mauve-purple from April through May in dense whorls at the upper leaf axils. Bloom duration is 4–6 weeks. Individual flower length is about twice that of Lamium maculatum, which carries flowers 0.5–0.75 inch (1.3–1.9 cm) long.
Detailed Descriptions
Flower Description
Dusky pink to mauve-purple; hooded two-lipped 1–1.5 inches (2.5–4 cm) long; dense whorls at upper leaf axilsFoliage Description
Medium green, broadly ovate, toothed, 3–5 inches (8–13 cm) long; opposite pairs on square stems; plain green without silver markingsGrowing Conditions
Sun Requirements
Requires 2-4 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
Plant in partial shade to full shade in average, moist, well-drained loam or clay soil at pH 6.0–7.5. Hardy in USDA zones 5–8. The species tolerates short dry periods once established but can enter summer dormancy with loss of foliage if drought is prolonged; consistent moisture through the growing season retains the leaves into late summer. Unlike the spreading Lamium maculatum and Lamium galeobdolon, the clump expands only from the crown and will not cover a large area from a single plant — more plants are needed for groundcover-scale coverage. No mid-season pruning or runner management is required.Pruning
Cut spent flower stems back to the basal foliage after bloom in June. Cut the clump back to ground level after frost in late autumn, or leave through winter and remove in early spring before new growth emerges. Division every 4–5 years in early spring rejuvenates older clumps whose centers open out.Pruning Schedule
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summerfall
Container Growing
✓ Suitable for container growing
Minimum container size: 3 gallons