Artemisia(California Sagebrush)

Plants in the genus Artemisia are commonly called wormwood, mugwort, and sagebrush—names that seem surprising for a member of the sunflower family (Asteraceae) even though there is no clear resemblance to sunflowers.

Artemisia Features

• Variations of size, habit, hue, and texture invite many uses in Sonoma County gardens.
• Silvery gray artemisias enhance nearby companion plants—especially those with dark green, deep maroon, and burgundy foliage.
• Care should be taken to set plants near others with similar cultural needs.
• Artemisias require no fertilizer, very little water, full sun or some light shade, and good drainage.
• Numerous species have a tolerance of cold and wet winters; planting on raised mounds assists good drainage.
• Artemisias dislike excess water and fertilizer, but irrigation is necessary to help establish shrubs; then, only occasional watering is generally all that is needed.
• Soft-stemmed species can be rejuvenated by cutting to the ground in autumn.
• Deer do not like their fragrance or flavor, but aphids do sometimes feed on early spring growth; otherwise, this rugged plant is quite pest resistant and not prone to any diseases.

Preferred Species

Of the hundreds of species, only a few are used in landscapes for casual, low maintenance, and arid gardens.

• Artemisia lactiflora (white mugwort), a clumping perennial native to western China,  bears deeply lobed, dark green foliage on lower stems that are topped with tall plumes of creamy white flowers in late summer to mid-autumn. The astilbe-like blooms make it useful as a bedding plant and for fresh cut or dried flowers. This species is one of the few in its genus that takes some shade and rich, moist soil. It grows up to 5 ft. tall and spreads 2-3 ft. wide.
• Artemisia ’Powis Castle’ is one of the most widely available cultivars in Sonoma County. It has airy, silvery gray, lacey foliage on woody stems that reach 3 ft. high by 4-6 ft. wide, but is easily shaped, even with severe pruning. In filtered sun, foliage becomes more gray-green; in full sun, silver hues dominate. Tough and versatile in low-water landscapes with other low-water plants.
• Artemisia pycnocephala ’David’s Choice’ (sandhill sage) is a native from Pt. Reyes and northern California beaches that thrives inland as well as in coastal areas. This 1-ft. high and wide small shrub is mostly rounded with some upright stems. It has the same easy care as other artemisias, needing very little water once established. After 2-3 years, its delicate blue-gray foliage becomes ragged and shrubs should be replaced.
• Artemisia schmidtiana ’Silver Mound’ (angel’s hair) forms a 1-2 ft. mound of soft, silky, silvery gray, finely cut foliage with small white or yellow flowers. The small size is suitable for rock gardens, the front of a border, and containers. Give it mostly dry, average soil.
• Artemisia stellerana ’Silver Brocade’ (beach wormwood, dusty miller) is a fast-growing, silvery spreader with leaves similar in size and shape to flatleaf parsley. At 2 ft. x 3 ft., it can be used to soften edges of walkways or cascade in hanging baskets. It takes full sun, little water, and contrasts easily with white, yellow, blue, reds, and maroon flowers or foliage.
• Artemisia dracunculus (French tarragon, true tarragon) is not considered a landscape plant but is a useful member of the genus. Planting in a container helps prevent unwanted sprawling and spreading. Because this 2-ft. high and wide perennial dies to the ground in winter, container plantings can be set aside for the cool-season months. This species is toxic to dogs and cats.

August 2023