Silver Spurge, gopher plant

Euphorbia rigida

silver spurge blooming at Academy Village

About the Plant

Native to the Mediterranean region, this evergreen plant has showy chartreuse flowers in late winter. Each plant has many stems, some laying almost on the ground, others standing more upright to 1-2 feet.

Grow silver spurge in full sun or light (but not heavy) shade. The lower stalks will often die after flowering. To keep the plant looking neat, cut off dead/dying stems at their base (see Allergy Alert below). Lanky stems can be cut back by half after flowering. This plant will reseed. If you wish to prevent this, remove flowers after they fade.

Allergy Alert: this plant causes contact dermatitis, similar to the rash caused by poison ivy, in sensitive individuals. Wear gloves and long sleeves when handling this plant. Wash tools used on this plant after use.

Wildlife value: attracts bees and other insects. Silver spurge and related plants are often called "gopher plant" because they are thought to repel gophers. Research has not substantiated this claim.

More Information

Horticultural information from ASU

ID Characteristics

This plant is in the Euphorbiaceae - the spurge family.
Silver spurge is a clumping plant with many leafy stems. The stems are more or less upright with the outer ones leaning almost to the ground, spreading to 2-3 feet. The stem is 1/4 inch wide. With leaves, it is about 3 inches wide for most of its length.
The evergreen leaves are arranged alternately. Each leaf is almost 1/4 inch wide at its attachment to the stem and narrows to a point. The leaves are 1.5 inches long and bend upward toward the top of the stem.
The flowers are held in a cluster at the top of the stem. Flowers in all species of Euphorbia are unusual. One female flower and several male flowers are held in a structure called a cyathia. There are three complete cyathium in the center of the photo above (click to enlarge) and several others around the edge of the photo. Pick one of those three and take a closer look.
Underneath each cyathia are two yellow bracts that give the flower cluster its color. Held in the center of those two bracts is the cup-shaped cyathia surrounded by 5 horn-shaped glands. The female flower (you can see the swollen ovary and the three-part stigma) protrudes from the center of the cyathia. It is surrounded by several male flowers that provide pollen.
When the female flower is pollinated, the ovary (developing fruit) begins to swell and the glands turn bright red. If you take a close look at the photo above, you can see two new cyathium developing on each side of a cyathia with the maturing ovary (the ones with the red glands).
Once the fruit has matured and dropped off, the bracts remain but turn brown. On this stem you can see some of the lower leaves turning brown and a portion of bare stem where some leaves have already dropped off. More leaves will gradually be lost and the whole stem will wither and die.