Euphorbia amygdaloides var. robbiae
mrs Robb's bonnet
Caucasus and northern Turkey (variety)
Overview
Euphorbia amygdaloides var. robbiae is an evergreen, rhizomatous perennial growing 18–24 inches (45–60 cm) tall and spreading 18–36 inches (45–90 cm) wide or more by underground runners. It forms rosettes of leathery, dark green, spoon-shaped leaves arranged in whorls toward the top of upright stems. In mid to late spring the stems are topped with broad, dome-shaped heads of small flowers surrounded by lime-green to yellow-green bracts that hold colour for many weeks. The plant grows in woodland and tolerates dry shade and root competition, spreading steadily to form colonies, which can become invasive in favourable conditions and may need containing. All parts exude a milky white sap that irritates skin and eyes and is toxic if eaten. Hardiness covers USDA zones 6–9. The dark evergreen rosettes hold through winter beneath the spring flower heads. It is grown as ground cover in dry shade, under trees and shrubs, and in woodland gardens where its spreading habit fills difficult ground.
Native Range
Euphorbia amygdaloides is native to Europe, western Asia, and North Africa, growing in woodland and shaded places. The variety robbiae originates from the Caucasus and northern Turkey and was introduced to British gardens in the early 20th century.Suggested Uses
Euphorbia amygdaloides var. robbiae is grown as ground cover in dry shade, under trees and large shrubs, and in woodland and gravel gardens. Its spreading habit fills awkward shaded ground where little else grows. The lime-green spring bracts contrast with darker shade foliage.How to Identify
Appearance
Size & Dimensions
Height1'6" - 2'
Width/Spread1'6" - 3'
Bloom Information
Flowering occurs in mid to late spring, usually April to May in the Northern Hemisphere. The true flowers are tiny and held within domed heads of lime-green to yellow-green bracts that keep their colour for many weeks into summer. The bracts fade to greenish-yellow as they age. Cutting back the spent flowering stems prompts fresh rosettes.
Detailed Descriptions
Flower Description
Lime-green to yellow-green bractsFoliage Description
Dark greenGrowing 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 Euphorbia amygdaloides var. robbiae in partial to full shade in most well-drained soils, including dry, poor ground under trees. It tolerates drought and root competition once established and spreads by runners, so it suits filling difficult shade but may need containing in smaller gardens. Water during the first season; mature plants need little care. Spent flower stems are cut out at the base after blooming, since each stem flowers only once. All parts release a milky sap that irritates skin and eyes on contact. The plant is generally healthy, though it can be prone to spurge mildew in some seasons.Pruning
Euphorbia amygdaloides var. robbiae is cut back after flowering, removing each spent flowering stem at the base, since those stems do not flower again. Fresh non-flowering rosettes carry the plant through to the next year. Runners are dug out to limit spread where a contained clump is wanted.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
summer
Container Growing
✓ Suitable for container growing
Minimum container size: 2 gallons