Western mugwort (Artemisia ludoviciana 'Valerie Finnis')

Overview

Artemisia ludoviciana ‘Valerie Finnis’ is prized primarily for its distinctive, silvery-white foliage that provides vibrant textural contrast in the garden landscape. This herbaceous perennial, commonly known as Western mugwort, maintains its color throughout the season, offsetting the greens and bright colors of neighboring plants. It is a member of the Asteraceae family, celebrated for its resilience once established.

While the species can sometimes spread vigorously, the ‘Valerie Finnis’ cultivar is generally regarded as more restrained in its rhizomatous growth habit, making it a more manageable feature. It thrives best when provided the environmental conditions it naturally prefers: poor, well-drained soil and full sun exposure.

Functionally, Western mugwort is valued for its hardiness, tolerating periods of drought and specific soil challenges. The aromatic foliage is an excellent addition when dried, though the flowers are generally considered insignificant. Gardeners utilize Artemisia ludoviciana ‘Valerie Finnis’ in areas where durable, low-maintenance silver accents are needed.

Fast Facts

• Plant Family: Asteraceae
• Plant Type: Herbaceous perennial
• Hardiness Zones: USDA Zones 5-10
• Size at Maturity:
  • Height: 1.5-2 ft
  • Spread: 1.5-2 ft
• Bloom Time: August to September
• Bloom Description: White
• Sun Exposure: Full sun
• Water Needs: Dry to medium
• Maintenance Level: Medium

How to Grow

For optimal success with Artemisia ludoviciana ‘Valerie Finnis’, planting should occur in full sun, which enhances foliage color and limits stem flopping. Excellent soil drainage is non-negotiable; this plant performs poorly and is highly susceptible to root rot in moist or wet soils. Plant in poor to moderately fertile soils for the best structure.

Watering should be sparse to medium once established, relying on the plant’s excellent drought tolerance. Fertilizing is discouraged, as rich soils encourage taller, weaker stems prone to lodging in the summer heat. In high humidity climates, general foliage decline can occur, necessitating careful placement away from overly damp areas.

To maintain a compact shape and encourage bushier growth, consider pinching back the stems in late spring before the heat sets in. If summer decline or flopping does occur, shearing the plant back revitalizes its appearance quickly. Propagation is straightforward via division, best done in late summer to early autumn.

Be mindful that Western mugwort can spread modestly via rhizomes and self-seeding. To prevent unwanted spread, promptly remove flower heads before they mature into seed. If containment is a major concern, planting soil barriers can help manage the rhizomatous habit, though ‘Valerie Finnis’ exhibits less aggression than some relatives.

Landscape Uses

The primary design function of Artemisia ludoviciana ‘Valerie Finnis’ is to provide stark textural and color contrast. Its silver-green foliage stands out beautifully against deep green evergreens, purple-leafed plants, or vibrant flowering annuals and perennials. It effectively breaks up mass plantings with its fine, airy texture.

Due to its potential to spread, this plant is often ill-suited for tight borders or formal herb gardens where control is paramount. Instead, Western mugwort excels in naturalized settings, dry rock gardens, or isolated areas where its spreading habit can be intentionally utilized to cover ground without encroaching on valued neighbors.

This Artemisia is an excellent choice for xeriscaping designs, especially in areas known for poor, dry soils where many other ornamental plants struggle. Groupings of Artemisia ludoviciana ‘Valerie Finnis’ create a shimmering, cool focal point, particularly during the bright afternoon sun.

Standout Features

Flower Qualities

• Insignificant
• Good Dried

Noteworthy Characteristics

Artemisia ludoviciana is native throughout North America, commonly called white sage due to its foliage appearance. This erect, rhizomatous perennial features aromatic, sage-like, lance-shaped leaves that are white woolly beneath, providing excellent garden texture. The cultivar ‘Valerie Finnis’ typically forms a neat clump of erect, non-woody stems reaching 18-24 inches tall, and its foliage is aromatic when bruised.

Tolerances

• Rabbit
• Deer
• Drought
• Erosion
• Dry Soil

Potential Problems

A primary concern when growing Western mugwort is summer foliage decline and stem flopping, particularly if the plant receives too much fertility or partial shade. The plant is highly susceptible to root rot if grown in poorly-drained or consistently moist soil conditions, a situation that must be avoided for the health of Artemisia ludoviciana ‘Valerie Finnis’. Gardeners must also manage its spread; unwanted propagation occurs via rhizomes or self-seeding, requiring vigilance in removal of spent flower structures.

Frequently Asked Questions

What hardiness zones is Western mugwort suitable for?

Artemisia ludoviciana ‘Valerie Finnis’ is suitable for cultivation in USDA Hardiness Zones 5 through 10.

How large does Western mugwort grow?

This perennial typically reaches a mature height between 1.5 and 2 feet tall, with a spread of 1.5 to 2 feet wide.

What sun exposure does Artemisia ludoviciana ‘Valerie Finnis’ need?

This plant requires full sun exposure to develop its best color and maintain sturdy structure.

When does Western mugwort bloom?

Western mugwort generally blooms from August through September, producing small white flowers that lack significant ornamental appeal.

Conclusion

The striking, silvery texture of Artemisia ludoviciana ‘Valerie Finnis’ makes it a dependable, low-water choice for adding architectural interest to challenging garden spots. While managing its spread via rhizomes and ensuring impeccable drainage is key, the durable nature of Western mugwort guarantees year-round visual appeal. Assess your local hardiness zone and confirm excellent drainage before incorporating this tough plant into your landscape design.

Companion Planting

When selecting partners for Artemisia ludoviciana ‘Valerie Finnis’, focus on plants that appreciate similar dry conditions and thrive in full sun. Grouping it with dark-leaved plants, such as Sedum ‘Autumn Joy’ which blooms later, or deep purple Salvia creates a dramatic visual pairing. Avoid highly thirsty, moisture-loving cottage garden standards, as the needs of Western mugwort for dryness will conflict.

For a cohesive meadow look, pair this Artemisia with drought-tolerant ornamental grasses like Blue Fescue (Festuca glauca) or other sun-loving silver foliage like Stachys. This combination leverages texture and color harmony while ensuring all plants share a preference for lean, well-drained substrate, maximizing the resilience of your design.

Propagation Tips

Propagation of Artemisia ludoviciana ‘Valerie Finnis’ is best achieved through plant division, which serves the dual purpose of multiplying the plant and renewing its vigor. Late summer or early autumn is the ideal time to divide the clump, allowing the separated sections to establish roots before winter dormancy sets in. Dig up the entire clump and gently separate the rooted sections, ensuring each division has sufficient roots and foliage mass.

Because the species can self-seed, seed propagation is an option, though it may result in less predictable foliage characteristics than the ‘Valerie Finnis’ cultivar exhibits. If you choose to collect seed, ensure the dry achenes are removed promptly after flowering finishes. Due to the rhizomatous nature, division remains the preferred, more reliable propagation method for maintaining the cultivar’s specific traits.