Upright Myrtle Spurge Euphorbia rigida

Rigid spurge is an erect, shrubby, evergreen perennial in the spurge family (Euphorbiaceae) that is native to southern Europe to Iran and northwestern Africa. It grows in a clump 1 to 2 feet tall and 2 to 3 feet wide.  It has blue-green leaves with chartreuse-yellow star-shaped flowers in the spring. The specific epithet, rigida, references its erect stems. This plant is very similar to Euphorbia myrsinites or myrtle spurge; however, it has prostrate stems.

Rigid spurge grows in poor, sandy and rocky well-drained loam soils in full sun but it will tolerate some shade. This plant is drought tolerant, poor soils tolerant, salt tolerant, and deer resistant. It is said to repel gophers, hence one of its common names. This plant self-seeds and can be propagated by seeds, division, or stem cuttings. It is winter hardy in USDA Hardiness Zones 7 to 11. It tends to be shorter lived in warm winter climates. 

The fleshy, blue-green leaves appear in close spirals. The foliage turns an interesting red to bronze color in the fall. Even though it is evergreen, in cold climates, the foliage will decline especially in wind. The flowers appear in the spring are small clusters of yellow-green star-shaped blooms and have chartreuse to bright yellow bracts.  As with all euphorbias, rigid spurge exudes a milky sap from the stems and leaves that can be toxic.

This plant achieved the Award of Garden Merit by the Royal Horticultural Society in the UK.  In other areas of its native range, it is considered a weed.

The rigid spurge will perform well in a rock gardens, coastal gardens, on banks or slopes, in xeriscape landscaping, or as a container plant for a patio or garden area.

Insects, Diseases and Other Plant Problems: Rigid spurge has no serious insect or disease problems. Remove spent flowers to prevent self-seeding. In undisturbed areas, this plant can become weedy.

Some people experience skin rashes from contact with the toxic sticky plant sap of euphorbias. Wear gloves when handling these plants. Euphorbias are toxic if ingested. Keep this plant out of the reach of small children and pets.

VIDEO Created by Laura Barth for "Houseplants, Succulents, and Cacti," a plant identification course offered in partnership with Longwood Gardens.

More information on Euphorbia.