Common Name: spurge
Type: Herbaceous perennial
Family: Euphorbiaceae
Zone: 6 to 9
Height: 1.50 to 3.00 feet
Spread: 1.25 to 2.50 feet
Bloom Time: April to May
Bloom Description: Green and yellow bracts
Sun: Full sun to part shade
Water: Dry to medium
Maintenance: Low
Suggested Use: Annual
Leaf: Colorful
Tolerate: Deer, Drought, Dry Soil, Shallow-Rocky Soil
Culture
Best grown in dry to medium, well-drained soils in full sun to part shade. Must have sharply-drained soils. Plants have good drought tolerance, but appreciate some moisture in dry summer periods. Plants are generally tolerant of poor soils, including rocky-sandy ones. Wet soils in winter can be fatal. Plants are considered to be evergreen in warm winter areas. Plants prefer a Mediterranean-type climate and may show some stress in hot and humid summers. Plants are not reliably winter hardy in USDA Zone 5 where they should be sited in protected locations with a root mulch. Pinch stems back to 6" in mid-spring immediately after flowering to encourage bushy growth. Wear gloves when working with this plant to avoid suffering harm from the toxic milky plant sap (eye inflammation, temporary blindness, skin rash/burning). No part of this plant should ever be ingested.
Noteworthy Characteristics
Euphorbia × martinii, sometimes called Martin’s spurge, is a naturally occurring hybrid subshrub which was discovered growing in the wild in southern France in the late 1800s, its parents being Euphorbia characias (Mediterranean spurge) and Euphorbia amygdaloides (wood spurge). Plants typically grow to 2’ tall. Tiny, apetalous flowers are enclosed in showy, petal-like, yellowish-green bracts which form numerous flower-like cups, each with a contrasting red eye, and bloom in dense elongate 4-5” clusters from spring into early summer. Narrow gray-green leaves are flushed with burgundy in spring. Stems are tinged with red. Broken stems exude a white milky sap that can be extremely toxic to human skin and eyes.
Genus name probably honors Euphorbus, physician to the King of Mauretania.
Hybrid name is presumably in reference to the person who first identified the hybrid.
'Ascot Rainbow' features variegated foliage in an array of greens and yellows, maturing to shades of red and orange with the onset of cooler evening temperatures in fall. Although mostly grown for its foliage, 'Ascot Rainbow' also produces terminal flower clusters with variegated bracts in spring. Individual plants will take on a dense, upright, clumping habit and reach up to 3' tall and 2.5' wide at maturity. Plant patent number PP21401 applies to this cultivar.
Problems
No known serious insect or disease problems. Noted for good resistance to powdery mildew. Gardeners with skin allergies should consider using gloves when working with this plant because of its toxic plant sap.
Uses
Beds and borders. Rock gardens. Small area ground cover. Edger. Best in groups. Containers.