Euphorbia marginata

Snow on the mountain is an annual forb in the spurge family (Euphorbiaceae) native to the Great Plains that has been cultivated in gardens and has escaped into the wild in many other states. It is weedy in disturbed areas including pastures, waste places, and can be found growing along roadsides. The genus name probably honors Euphorbus, physician to the King of Mauretania. The specific epithet is in reference to the white leaf margins.

These plants grow on a single stem 1-3 feet tall. They prefer full sun and tolerate poor soils as long as they are well-drained. In hot summer climates some protection from the hot afternoon sun may be needed. Too much shade will cause the plants to be floppy. They are deer and drought-resistant. Plants will reseed themselves in the garden.

The attractive gray-green leaves are edged in white near the stem ends and sometimes all white. The flowers are long-lasting and occur in clusters from summer to fall. 

Use this plant in naturalized areas, borders or as an annual ground cover for sunny dry areas. 

Stems and leaves contain a milky latex sap that can cause contact dermatitis for some be sure to wear gloves.

Insects, Diseases, and Other Plant Problems: No significant problems. Watch for aphids. Can be weedy.

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