Euphorbia amygdaloides subsp. robbiae
Common Name: spurge
Type: Herbaceous perennial
Family: Euphorbiaceae
Native Range: Europe, southwestern Asia
Zone: 6 to 8
Height: 1.50 to 2.00 feet
Spread: 0.75 to 1.50 feet
Bloom Time: April to June
Bloom Description: Yellow
Sun: Full sun to part shade
Water: Dry to medium
Maintenance: Low
Suggested Use: Naturalize
Flower: Showy
Tolerate: Rabbit, Deer, Drought, Dry Soil, Shallow-Rocky Soil, Air Pollution

Culture

Best grown in dry to medium, well-drained soils in full sun. Appreciates some afternoon shade in hot summer climates. However, clumps tend to open up and lose their attractive shape in too much shade. Must have sharply-drained soils. Wet soils, particularly in winter, can be fatal. Plants are tolerant of some poor soils, including rocky-sandy ones. Plants generally prefer a Mediterranean-type climate and may show some stress in hot and humid summers.

Noteworthy Characteristics

Euphorbia amygdaloides, commonly called wood spurge, is a bushy, evergreen, compact, free-branching euphorbia that typically grows in an upright rounded mound to 12-20” tall. It is native to woodland margins in Europe, western Asia and the Mediterranean.

Spatulate to obovate matte green leaves (to 3” long) are purple tinted beneath. Lower leaves are alternate along the stems with the upper leaves in whorls. Leaves retain good green color throughout summer, but acquire attractive purple-burgundy tones with the onset of cooler fall weather. Broken stems exude a white milky sap that can be a significant skin irritant and is poisonous if ingested. Stems are topped in spring (April to June in St. Louis) by an inflorescence (to 8” tall) containing yellow-green flowers borne in cyathia. The true flowers lack sepals and petals and are inconspicuous (single pistillate flower is ringed by several staminate flowers). However these flowers are subtended by long-lasting, yellow-green, leaf-like floral bracts which are exceptionally showy and contrast well with the plant foliage.

Species plants will self-seed in the garden unless spent flowers are deadheaded prior to setting seed.

Subsp. robbiae, commonly known as Mrs Robb’s hatbox, is distinguished from the species by having broader, dark green leaves in rosettes with a more rapid rhizomatous spread. Makes an excellent ground cover.

Subspecies name and common name, robbiae, are in reference to plant collector and botanist Mary Ann Robb (1829-1912) who discovered this plant in a woodland area near Istanbul, Turkey and brought some cuttings and seeds back to her garden in Liphook, Hampshire in a hat box in 1891.

Genus name probably honors Euphorbus, physician to the King of Mauretania.

Specific epithet comes from the Latin word amygdalinus meaning almond-like.

Common name of spurge comes from the Latin word purgans meaning purgative in reference to an old-time medicinal use of the plant.

Problems

No serious insect or disease problems. Use gloves when working with this plant. Some gardeners experience skin rashes from contact with the toxic plant sap of euphorbias.

Garden Uses

Beds, borders and rock gardens.