White Artemisias - Herb of the Week

Herb of the Week Artemisia – White Artemisias

This week I decided to focus on two more artemisia varieties that are mostly white.  They are perfect in a moon garden or as an accent plant in a flower garden.  The first is Artemisia ludoviciana this is a tall kinda leggy and wild looking plant, but it makes great wreaths and decorations because it dries so attractively.  The second is a more rounded less wild shape called Artemisia schmiditiana. Artemisia schmiditiana is especially attractive as a background behind bight colored flowers like calendula or marigolds or alongside purple flowers.

Artemisia ludoviciana

Artemisia ludoviciana 'Silver King' is native to the western United States although I grew it quite well beginning with my first herb garden here in Illinois. It is commonly called white sage because of the appearance of its foliage: lance-shaped leaves (to 4” long) are silver-white, and somewhat sage-like in appearance. 'Silver King' is a compact cultivar that features leaves and stems that are somewhat more slender than the species. It is a generally upright perennial that is grown for its attractive foliage that adds texture and contrast to gardens.  Not only is it nice in the garden, but I used it dried to create wreath bases and to make tree shaped table decorations that I covered with holiday ornaments at Christmas time.  Another popular cultivar is ‘Silver Queen.’

Generally referred to as white or gray sagebrush, this is native to the United States and Canada and is listed as a weed in the United States, but then most herbs are!  This plant can be weedy or invasive and is  known by one or more common names in different places. Most include sage or sagebush or sage wort.

Many subspecies are found only in the western United States. This is a rhizomatous perennial plant growing to heights between 1 to 3 feet in height. The stems bear linear leaves up to 4 inches long, but I must admit mine were long, but never that long, closer to 2 inches was most common.  The stems and foliage are covered in woolly gray or white hairs. The reason I grew this plant was that it was often used by different Native American groups for a variety of medicinal, veterinary, and ceremonial purposes.

Artemisia ludoviciana has become a popular garden plant, although it has a tendency to be aggressive in some gardens. The most commonly grown forms are the selections A. ludoviciana 'Valerie Finnis' and 'Silver Queen', which are both hardy to USDA zone 4. Spreading by rhizomes, Prairie Sage can form dense colonies that give a distinctive silver-green accent to large plantings on sunny sites with mostly dry soil. Its stems and foliage are covered with woolly gray or white hairs and topped by nodding clusters of yellowish disk flowers that bloom through summer.

To Grow

The plants reach heights of 3’ and are easily propagated by rhizome cuttings in spring, tip cuttings in early summer or by division of mature plants. Prairie Sage, also called White Sagebrush, is aggressive and rhizomatous and therefore may not be suitable for small landscape plantings.

This subspecies seems very drought tolerant, and grows in dry, light soils. A very wide-ranging species adapted to many temperature ranges and rainfall patterns. Artemisia ludoviciana tolerates alkaline soil, sand, clay, seasonal flooding, high traffic(people walking on it) and deer. I placed it by the garage door, in the nasty patch of soil between the paved drive and the garage and harvested it almost down to the ground each fall.

Artemisia schmiditiana

Artemisia schmiditiana is the most common found in herb gardens in Illinois.  This is the species known most commonly as Silver Mound, Mugwort, or Wormwood. This cultivar is best known for its bug repelling qualities.   Once can take the dried leaves and wrap them inside a coffee filter to form a sort of "pod" and place them under furniture cushions as a natural way of repelling fleas from their home.

For a distinctive accent in borders or an unusual ground cover, we recommend this slinky silver foliage. 'Silver Mound' takes drought and cold, and aromatic oils make the leaves deer resistant. It also makes a fine addition to fresh or dried bouquets. A good companion for Mediterranean plants like Lavenders, Rosemary and Species Tulips. Plants form tidy clumps in average soil that is well-drained.

This is the 'Nana' variety

A native to Japan this has been naturalized in the United States and is hardy to Zone 4. A large genus of plants, most of which are grown for their silver foliage and durable dispositions. They are invaluable for their ability to set off both foliage and flowers of a wide range of hues and are, or should be, a staple of borders where the dry heat they crave is common. In the South, where heat is combined with humidity, most Artemisias will rot away or die out, except 'Powis Castle'.

Striking and distinctive with finely cut silver leaves that form a dense mound of foliage. Very showy against green foliage of other garden plants.  There is a popular variety called 'Nana' that grows just 3 inches tall forming a 1-foot-wide mound of fine silver leaves.  This makes a great border plant.

All versions of this artemesia are great at repelling insects.  I use it in my insect repellent formulas and the earthy scent is much less harsh on the nose if you mix in a bit of lavender.

To Grow

Just like its counter part above, this plant is drought tolerant and prefers a sandy well drained soil.  It has a 1 to 1 ½ foot height and about the same for spread.  If you harvest it regularly you can keep it in a nice mounded shape as it is not as hast of as furious a grower as Sagebrush.

Propagate by cuttings, division or separation. Divide in spring or fall. Make cuttings in summer.

Avoid watering as moist soil and high humidity cause rot. Give the plants space for good air circulation. Remove blooms  which are rather insignificant to prevent foliage from deteriorating and losing its unique scent.  When plants open up in summer, cut back to new growth. This can be done gradually if drastic cutting detracts from garden aesthetics.