Plan de Análisis

Jelitto and Schacht’s Hardy Herbaceous Perennials (1990) lists twenty-seven species of artemisias, including annuals, biennials, and perennials. Graham Stuart Thomas (1990) describes eleven gardenworthy perennial artemisias, most having the recognizable qualities of silver or gray aromatic foliage with soft hairs on one or both sides of the leaves and small yellow composite fl owers. Artemisias have long been cultivated for other qualities too, particularly for their medicinal or herbal properties. They are more suited to the herb garden than the perennial border, but some are hand-some, erect semi-woody small shrubs that deserve a place as an ornamental, growing best in hot, dry situations in sandy soil. The best ones to incorporate in the border are A. ‘Powis Castle’, A. ‘Huntington’, and A. lactifl ora Guizhou Group. Almost all the others we list are invasive and require control to maintain their place in the society of plants.

You can always fi nd a spot for artemisias. Combine A. ludoviciana ‘Silver Queen’ with alstroemeria in a parking strip and throw in a bit of crocosmia. Some work wonders in a fresh or dried fl oral arrangement. ~ Susan Buckles Scientifi c Name: After the Greek goddess Artemis.

Common Name: Wormwood, mugwort.

Origin: Europe, North America, North Africa, Asia.

Preferred Conditions: Poor to average, well-drained, light soil. Drought tolerant once established. Tolerant of rocky, dry exposure or cool, foggy coastal climates.

Adaptable to many garden environments. Doesn’t do well in wet, soggy areas.

Light: Sun.

Planting: A handful of soft rock phosphate will boost root growth. Compost or sand can be added to heavy clay soils to improve the tilth.

Management: Large shrubby artemisias should be cut back to six to twelve inches from ground level in spring, and the dwarf forms just given a trim to tidy up. You can cut some back to prevent blooming (e.g., A. ludoviciana ‘Valerie Finnis’, A. ‘Powis Castle’, A. alba ‘Canescens’).

Some cultivars can be helped with gravel or crushed rock mulch. Herbaceous forms should be cut down completely when foliage is dead. All except A. lactifl ora have inconspicuous fl owers at best. At worst, fl owers are ugly and detract from the foliage; fl owering stems are best removed as soon as they appear.

Propagation: Division in spring. Most are easily divided (exceptions are A. absinthium

‘Lambrook Silver’ and A. ‘Powis Castle’). Take cuttings in spring; and for the woody forms, cuttings only.

Pests and Diseases: Mildew, rust (A. lactifl ora), aphids (A. absinthium ‘Lambrook Silver’, A. ‘Powis Castle’).

Companions: Ornamental grasses, lilies, white fl owers, allium, aster, sedum, nepeta.

Notes: Don’t fertilize, and artemisias will live longer in the garden. This includes manure mulch. A hard prune in the fall can kill most of the shrubby forms.

Artemisia ludoviciana ‘Valerie Finnis’.

Artemisia

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Species and Cultivars

Height/

Spread

USDA Hardiness Zone

Flowers

(bloom time) Foliage Comments

abrotanum 3–4ft × 2ft 5–10 Yellowish,

insignifi cant (M–L)

Woody, multibranched, gray-green, fernlike, aromatic subshrub

Southernwood, prune in spring, may benefi t from a midsummer clip, RHS Award absinthium 2–4ft × 2ft 5–10 Yellow-gray (M–L) Silvery gray-green,

coarse, feathery, aromatic

Common wormwood, keep pruned for best shape, evergreen a. ‘Lambrook Silver’ 2½–3ft × 3ft 5–10 Grayish white sprays

(M)

Delicate and airy clumps of silky-gray divided leaves

Cut back fl ower shoots, evergreen, RHS Award alba ‘Canescens’ 10in × 18in 5–10 Small, yellow (M) Silver, threadlike, and

lacy on woody stems

Good groundcover, needs good drainage, remove fl owers, RHS Award

Artemisia ‘Huntington’ with Agastache ‘Apricot Sunrise’, ×Solidaster luteus, Ruta graveolens, a helianthus cultivar in fl ower and Helianthus maximiliani (above).

Artemisia

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Species and Cultivars

(bloom time) Foliage Comments

‘Beth Chatto’ 15–18in × 18in+

5–9 Insignifi cant (M) Silvery, low, dense Good groundcover, needs good drainage

‘Huntington’ 3–4ft × 3ft+ 6–10 Tiny, insignifi cant (L)

Lacy, loose, silver leaves, upright, bushy, woody plant

Well-drained, cut back to 6in in spring as new growth starts

lactifl ora 4–6ft × 2ft 5–10 Creamy-white

plumes on sturdy erect stems, fragrant (M–L)

Dark green, ferny, paler beneath

White mugwort, looks like a tall astilbe, prefers heavier moisture-retentive soil, herbaceous perennial, RHS Award

l. Guizhou Group 4–6ft × 2ft 5–10 Ivory-white on dark purple stems, fragrant, astilbelike plumes (M–L)

Blackish green, dissected, coarse, on black stems

Likes a richer, moist soil, tolerates part shade, herbaceous perennial

ludoviciana 4ft × 3ft 5–10 Yellow-white,

insignifi cant (M)

Silver-gray, willowy, aromatic, bushy on slender erect stems

Western mugwort, this and its selections are best artemisias for cutting, all are herbaceous perennials l. ‘Silver King’ 2–3ft × 2ft 5–10 Silver-white,

insignifi cant (M–L)

Long, narrow, silver-white

Spreading habit, cut to ground in fall l. ‘Silver Queen’ 2½–3ft × 2ft 5–10 Insignifi cant, seldom

produced (M–L)

Low mound, silver-white

Best of the

ludovicianas for cut fl owers, RHS Award l. ‘Valerie Finnis’ 1½–2ft × 2ft 5–10 Tiny, insignifi cant

(M)

Large, silver-white, felty, jagged

Cut mature plants to ground midsummer, will reappear at lower height, RHS Award

‘Powis Castle’ 2–3ft × 2ft+ 6–10 As above Finely cut, silver-gray, shrubby woody plant

Responds well to pruning in late winter to 1ft. May be short-lived in rich soils and hard winters, RHS Award

schmidtiana ‘Silver Mound’

1ft × 1ft 5–10 White, insignifi cant (M)

Silver, velvety, fernlike, aromatic, compact

May need cutting back in midsummer, short-lived, likes good drainage, herbaceous perennial

stelleriana 1½–2½ft ×

2ft+

5–10 Tiny, yellowish on gray stems (M)

Grayish white, felty, chrysanthemumlike, evergreen in mild climates

Beach wormwood, rock garden plant, sensitive to winter wet, semi-herbaceous perennial, cut back in spring

s. ‘Boughton Silver’ (syn. ‘Silver Brocade’)

6–10in × 2ft+ 5–10 White, insignifi cant (M–L)

Silver with a hint of green, felty, evergreen in mild climates

Groundcover or edging plant, like it dry, compact versicolor 1ft × 3ft 5–10 Insignifi cant (M) Pale, gray, curly with a

blue-green cast, woody at base

Dwarf, foliage dries well for arrangements

Artemisia

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