How to Grow and Care for 'Silver Mound' Artemisia

'Sllver Mound' is a popular named cultivar of Artemisia schmidtiana, one species within the large Artemisia genus of hardy shrubs and perennials The genus includes more than 200 species, including plants that go by the common names of wormwood, sagebrush, and mugwort. The 'Silver Mound' cultivar of A. schmidiana is a mounding plant with attractive lacy silver foliage that is often used as an edging plant. It has two notable advantages over other Artemisia varieties—'Silver Mound' tolerates hotter temperatures than most other varieties, and it doesn't spread invasively like some of its relatives.

While 'Silver Mound' does produce inconspicuous yellow blossoms in the summer, they are typically removed to keep the plant focused on producing foliage, not flowers. This is an excellent plant to use as a cool contrast to other perennials with bright flowers in a container or garden bed.

Like many other plants in its family, 'Silver Mound' is toxic to pets and people when consumed.

'Silver Mound' Artemesia Care

Although its ferny foliage gives it a delicate appearance, looks can be deceiving. For the most part, 'Silver Mound' is an easy plant to care for, and not especially troubled by many pests or diseases.

This plant is a good choice for low-water gardens, since it has a high tolerance for drought. It also does well in polluted city environments and in soils containing road salts. It's often used as an edging plant where its fine texture and silver color makes a good contrast with more dramatic plants. It is a good choice in Mediterranean-style gardens as a companion for fragrant herbs, as well.

You can show off 'Silver Mound' in outdoor containers, where it serves as a "filler" backdrop to taller thriller and cascading spiller plants. Mix it with cool-hued flowers for best effect.

Light

'Silver Mound' prefers a full-sun location, but it will tolerate a little bit of shade, especially in hot climates.

Soil

Unlike many other perennials, 'Silver Mound' not only tolerates somewhat infertile soil, it actually does best when planted in ground that isn't too rich in nutrients. It will do equally well in clay or sandy soil, as long as it drains well. However, soil that holds onto water is a guaranteed method for killing your Artemisia, as the plant won't stand wet roots for long.

Water

'Silver Mound' requires watering only during periods of no rain, or if the top three inches of soil dry out. This drought-tolerant perennial quickly succumbs to root rot if overwatered, so take care to let the soil dry out thoroughly before providing supplemental water.

Temperature and Humidity

'Silver Mound' is happiest in hot, dry weather, but it will tolerate some humidity. It can survive winter temperatures well below zero, although it will die back to the ground when the weather stays below freezing for long. It will return in the spring, however. In mild-winter areas, 'Silver Mound' is evergreen.

Fertilizer

'Silver Mound' needs no extra fertilizer; in fact, it will require less care if the soil is kept poor. At most, work a little compost into the soil around the plant in the spring. Overfeeding this plant leads to floppiness and loss of its naturally mounding shape.

Types of Artemisia

There are many species of Artemisia. Some are considered weeds, others are commonly grown as garden plants, and still others have herbal uses.

• A. vulgaris, known as mugwort, often grows as a weed along roadsides. Mugwort has been used in traditional herbal medicine.
• Sagebrush (A. tridentata) is another weedy Artemisia.
• A. dracunculus is the botanical name for the common herb tarragon, popular in cooking.
• The alcoholic drink absinthe is made with A. absinthium.

In terms of types planted for their foliage, Artemisia 'Silver King' (A. ludoviciana) is taller than 'Silver Mound.' It is often dried and used to make wreaths. Artemisia 'Powis Castle' is another taller cultivar used in landscaping.

Pruning

You can promote your 'Silver Mound's' rounded shape by pinching back the growing tips occasionally during the spring.

If your plant starts to flop over during the summer, leaving a hole in the center of the foliage, prune it by a third, and reduce watering. The plant should soon spring back to its normal mounded shape.

Most gardeners also snip off the small flowers as soon as they appear, as this encourages the plant to maintain its attractive foliage without spending energy on blossom and seed production.

Propagating 'Silver Mound'

'Silver Mound' is most often propagated by division. Every two to three years, dig the clump up in the late fall. Use your shovel to gently separate the clump into two or three sections, gently teasing apart the roots with your fingers. You can then replant each section as a new plant. This keeps your 'Silver Mound' plants healthy and helps prevent legginess or floppiness.

Overwintering

While 'Silver Mound' will die back naturally once the severe chill of winter hits, it's best to protect the plant by pruning it down to 4 inches or so before freezing temperatures set in. In the coldest areas, cover the pruned plant with a few inches of mulch for extra protection.

Common Problems With 'Silver Mound' Artemisia

'Silver Mound' is an easygoing plant for the most part. Few insects bother it, and deer and rabbits generally leave it alone. It's fairly disease-resistant as well. As long you refrain from overwatering, plant 'Silver Mound' in a dry, sunny spot, and don't give much fertilizer, it will usually thrive. The following are two common issues, however.

Floppiness

One of the most common problems with 'Silver Mound' is the plant going floppy, leaving a hole in the center of the mound. This is most often caused by overwatering, but can also be caused by too much fertilizer or too much shade. To correct the problem, prune away several inches from all of the plant's stems, and then cut back on water. Let the soil dry out for three inches down between waterings. If you've been fertilizing the plant, stop; this is a plant that prefers poor soil.

Yellowing or Wilting Leaves

A wilted, yellowed 'Silver Mound' has generally been overwatered. While it's tough to save this plant once root rot sets in, if you act quickly to reduce watering, the plant may recover.