Loosestrife (Lysimachia punctata 'Alexander')

Overview

Lysimachia punctata ‘Alexander’, commonly known as Loosestrife, stands out in the garden due to its striking green and white variegated foliage, which often shows pink tinges in the spring. This patented cultivar provides vibrant color contrast against its upright stems, topped by cheerful yellow, cup-shaped blooms from May into June. While related to the genus Lysimachia, it is important to note this plant is not the aggressive ornamental Lythrum salicaria.

As a rhizomatous herbaceous perennial, this Loosestrife readily forms colonies, making it excellent for filling medium-to-large gaps in moist garden areas. It is valued for its low maintenance requirements and its ability to thrive where moisture is consistent. Gardeners should appreciate the aesthetic value Lysimachia punctata ‘Alexander’ brings through both flower and leaf texture.

Its ability to spread means planting location is key; utilize it where its colonization is desired, such as in naturalized areas or along water features. When provided with rich, moist soil, the variegation remains crisp and healthy, enhancing borders and cottage garden scenes throughout the growing season.

Fast Facts

• Plant Family: Primulaceae
• Plant Type: Herbaceous perennial
• Hardiness Zones: USDA Zones 4-8
• Size at Maturity:
  • Height: 1-2 ft
  • Spread: 0.75-1 ft
• Bloom Time: May to June
• Bloom Description: Yellow
• Sun Exposure: Full sun to part shade
• Water Needs: Medium to wet
• Maintenance Level: Low

How to Grow

For optimal establishment, plant Lysimachia punctata ‘Alexander’ in the spring or fall. It thrives in moist, humusy, well-drained soils, performing best when sited in full sun or light shade. If growing in hotter climates, such as the St. Louis area, afternoon shade is highly recommended to prevent foliage scorch.

Maintenance for this Loosestrife is generally low. Ensure consistent moisture, especially if aiming for the best performance and clearest variegation; dry soils can cause the variegated foliage edges to turn brown. Fertilization is usually unnecessary if the soil is already fertile and rich.

The plant will spread via rhizomes, forming dense colonies over time, though this cultivar is noted as being less aggressive than the species plant. Pruning is rarely required, but spent flower stalks can be trimmed back after blooming concludes to maintain a tidy appearance.

Monitor spread carefully, as it is self-seeding in ideal conditions. Because ‘Alexander’ is a patented cultivar, it will not come true from seed and reliance should be placed on division or purchasing new stock for propagation rather than collecting seed.

Landscape Uses

Lysimachia punctata ‘Alexander’ is highly recommended for areas needing consistent moisture, such as pool peripheries, along streams, or in wild gardens where it can naturalize freely. Its upright habit and bright foliage work well in cottage gardens or as robust edging along established borders.

Its spreading nature makes it a superb groundcover for bank stabilization or in open woodland settings where it can fill space without competing with fine textured perennials. However, due to its reliable rhizomatous spread, gardeners must exercise caution. Never plant this vigorous Loosestrife near delicate or highly prized perennials, as it may encroach upon their space aggressively.

Consider pairing this variegated foliage with deep green hostas or dark purple foliage plants to maximize the visual contrast provided by the yellow blooms and white margins of Lysimachia punctata ‘Alexander’.

Standout Features

Flower Qualities

• Showy
• Good Cut

Noteworthy Characteristics

Lysimachia punctata, commonly called loosestrife, is native to central/southern Europe and Turkey, but has over time escaped gardens throughout many parts of the northern U.S., particularly in the northeastern states, where it has naturalized in waste places, ditches and along roadsides. It is a rhizomatous perennial that grows to 3’ (infrequently to 4’) tall on stiff upright stems clad with pubescent, ovate to lance-shaped, medium green leaves (to 3” long) in whorls of 3 or 4 (occasionally opposite). Genus name honors King Lysimachus (661-281 B.C.), Macedonian King of Thrace and is derived from lysimacheios which was the ancient Greek name of a plant in this grouping. The cultivar ‘Alexander’ is famous for its distinctive green and white variegated foliage that emerges in spring with pink tinges.

Potential Problems

No serious insect or disease problems are typically reported for this plant. While Lysimachia is susceptible to rust and leaf spots, maintenance of good air circulation and appropriate watering practices can minimize these fungal issues. Gardeners must closely monitor spread, as this plant has the potential to move aggressively via its root system, even if deemed less invasive than other loosestrifes.

Frequently Asked Questions

What hardiness zones is Loosestrife suitable for?

Lysimachia punctata ‘Alexander’ is suitable for USDA Hardiness Zones 4 through 8. Ensure your location falls within this range for reliable perennial performance.

How large does Loosestrife grow?

This herbaceous perennial typically reaches a height between 1 to 2 feet, with a spread ranging from 0.75 to 1 foot wide.

When does Loosestrife bloom?

Lysimachia punctata ‘Alexander’ produces its characteristic bright yellow flowers primarily from May to June.

What sun exposure does Loosestrife need?

This plant succeeds in conditions ranging from full sun to partial shade, although some afternoon shade is beneficial in hotter parts of its range.

Conclusion

The variegated foliage and dependable yellow blooms make Lysimachia punctata ‘Alexander’ a fantastic, low-maintenance addition for mid-summer interest in the garden. This specific Loosestrife cultivar offers manageable spread and strong visual appeal compared to its wilder relatives. Check your USDA zone compatibility today and plan to plant this energetic perennial in a consistently moist location to enjoy its best variegated display.

Companion Planting

When selecting companions for Lysimachia punctata ‘Alexander’, prioritize plants that also enjoy medium to wet soil conditions and can handle similar sun exposures of full sun to part shade. This allows for unified maintenance across your planting beds. Consider pairing it with darker-leaved plants to make the yellow flowers and variegated foliage truly pop.

Excellent choices include darker varieties of Hosta, which appreciate similar moisture levels and benefit from afternoon shade enjoyed by the Loosestrife. Tall, moisture-loving Iris or moisture-tolerant Astilbe provide differing flower shapes and textures that complement the upright whorled pattern of the Lysimachia.

If using this plant near a pond or stream edge where moisture is abundant, consider Iris pseudacorus or various marsh marigolds (Caltha) for a cohesive, seasonally interesting water garden scene.

Seasonal Care Calendar

Spring preparation involves cleaning up any old winter debris and monitoring the emergence of the new variegated shoots. This is the best time to amend the soil lightly with compost if fertility needs boosting, as Lysimachia grows best in moist, fertile soils.

Summer is the primary growing and blooming season; ensure watering remains consistent, especially during dry spells, to prevent the foliage from browning at the edges. Deadheading spent yellow blooms is optional, though it can improve the summer appearance.

In late fall or early winter, the foliage of this herbaceous perennial will die back. Cut the remaining stems down close to the ground before spring growth begins, thereby tidying the bed for the next season’s emergence of the striking Lysimachia punctata ‘Alexander’.