Plants grown for their foliage effect add a special touch to the flower garden. This is especially true during the transition between summer and fall when flower color in the garden is lacking. Gray foliage intensifies the color of nearby flowers and other foliage and ties together almost every color combination imaginable.
The genus Artemisia offers gardeners a wide array of species to choose from for adding gray foliage effect to the flower garden. All species share the same cultural requirements of full sun and well-drained soils. Heavy, wet soils will result in poor performance and quite often death of the plant. Disease and insect pests are rare when given proper cultural requirements. When excessive humidity occurs, leaf rust can be a problem.
Artemisia abrotanum, commonly called southernwood, old-man, or lad's love grows up to 4 feet tall and 1 1/2 feet wide. It is hardy in USDA hardiness zones 5 to 9. The foliage is finely divided, creating a feathery texture and, like many of the artemisias, the foliage is aromatic when rubbed or crushed. The plant flowers in mid to late summer; however, flowers are not ornamental. Old-man can be used effectively in the flower border.
Artemisia absinthium 'Lambrook Silver' has silver colored foliage. It grows 2 1/2 feet tall and spreads 2 feet. This variety should be trimmed during the summer to promote branching and prevent the plant from flopping. It is hardy for zones 4 to 9. It is utilized in the perennial border as well as in herb gardens. The foliage is excellent used in wreath making.
Artemisia x'Powis Castle' is a hybrid between Artemisia arborescens and Artemisia absinthium. 'Powis Castle' has fine textured foliage and grows to a height of 3 feet with a spread of 4 feet. It is hardy in zones 5 to 9.
Artemisia lactiflora, white mugwort, is somewhat of an oddity among the artemisias. It has the coarsest foliage of the ornamental artemisias and has attractive creamy white flowers in late summer. White mugwort can grow 4 to 6 feet tall with a spread of 2 to 3 feet. It is effectively used as a background plant in combination with other fall blooming plants. Flowers can also be used in fresh and dried arrangements. This species is hardy in zones 4 to 8.
Artemisia ludoviciana, commonly known as white sage or Louisiana artemisia, grows 2 to 3 feet tall and forms a broad spreading clump. This species is suitable for massing and filling in the voids in the flower garden. Its foliage can be dried and used in arrangements as well. Cultivars such as 'Latiloba', 'Silver King', 'Silver Queen', and 'Valerie Finnis' make excellent garden additions. White sage and its cultivars are hardy in zones 5 to 8.
Roman wormwood, Artemisia pontica, is a low growing species reaching just 18 inches tall with a similar spread. Roman wormwood can be invasive and should be used in areas where a quick ground-cover is needed. It is hardy in zones 4 to 9.
Artemisia schmidtiana 'Nana' or 'Silver Mound' is probably the most commonly grown artemisia. It grows just 12 to 18 inches tall and forms a rounded mound of foliage 18 inches in diameter. This plant is utilized as a specimen plant in the perennial border or in the rock garden. The most common problem associated with 'Silver Mound' is the tendency for the clump to open in the middle. This occurs where soils are too fertile and moist. For best performance of this variety, do not fertilize and grow in full sun. Plants can also be trimmed back prior to flowering to prevent opening up. This species is hardy for zones 3 to 7.
Artemisia stelleriana, beach wormwood, old woman, or dusty miller, has a creeping to mounded habit. It grows 1 to 2 feet tall and 2 to 3 feet wide. The foliage resembles chrysanthemum leaves or the annual dusty miller. This species can be used effectively as a specimen plant or in massed plantings. It is hardy in zones 3 to 8.
The foliage of plants adds just as much to the garden as the color of the flowers. In the case of artemisia, its foliage is the most attractive feature. Give some of the less common species a try in your garden. I'm sure you'll like the effect.
This article originally appeared in the August 12, 1994 issue, p. 129.