Shasta daisy (Leucanthemum × superbum 'Alaska')

Overview

The Leucanthemum × superbum ‘Alaska’, widely known as the Shasta daisy, is a timeless staple in the summer garden, celebrated for its bright, classic white flowers contrasting against cheerful yellow centers. This robust herbaceous perennial provides reliable, long-lasting color, making it invaluable for creating established cottage garden aesthetics. The Leucanthemum × superbum ‘Alaska’ is prized not only for its beauty but also its relatively low maintenance requirements once established in suitable conditions.

Developed by Luther Burbank, this hybrid consistently delivers showy blooms from mid to late summer, attracting the eye from borders and providing excellent material for fresh arrangements. Its ease of growth in average soils, combined with its tolerance for drier conditions, cements the Shasta daisy’s position as a consistent performer adaptable to many garden situations.

Fast Facts

• Plant Family: Asteraceae
• Plant Type: Herbaceous perennial
• Hardiness Zones: USDA Zones 5-9
• Size at Maturity:
  • Height: 1.5-3 ft
  • Spread: 1.5-2 ft
• Bloom Time: July to August
• Bloom Description: White with yellow centers
• Sun Exposure: Full sun
• Water Needs: Dry to medium
• Maintenance Level: Low

How to Grow

The ideal location for Leucanthemum × superbum ‘Alaska’ plants is one receiving full sun, though they can tolerate light afternoon shade, especially in very hot climates. Good soil drainage is absolutely essential; wet soils, particularly during winter dormancy, can prove fatal to these perennials. Plant in average, well-drained soils amended to ensure moisture moves through freely.

Watering requirements are dry to medium once established; allow the soil to dry slightly between waterings rather than keeping it consistently moist, reflecting their drought tolerance. Fertilization is generally not required if planted in reasonable garden soil. Maintenance involves deadheading (removing spent flower heads) to encourage spot blooming throughout the summer season.

To maintain vigor and prevent overcrowding, plan to divide the clumps of Shasta daisy every two to three years. Since these plants are somewhat short-lived, a routine division helps ensure long-term health. Some gardeners opt to cut the stems back to the basal foliage immediately after the main flush of flowers fades to conserve plant energy.

Landscape Uses

Shasta daisies provide dependable, long-lasting summer color and are fundamental components of the traditional perennial border and cottage garden schemes. Their clean white faces pop beautifully against a backdrop of lush summer greenery. They are equally valuable in the cutting garden due to their long vase life as a fresh cut flower.

Consider using Leucanthemum × superbum ‘Alaska’ in middle or back borders where their 1.5 to 3-foot height adds structure without overwhelming shorter neighbors. They mix well visually and culturally with plants that enjoy similar sun and drainage needs, such as Lavender, Coneflowers (Echinacea), and ornamental grasses. They also perform well in rock gardens or large containers where drainage can be carefully managed.

Standout Features

Flower Qualities

• Showy
• Good Cut

Noteworthy Characteristics

Leucanthemum × superbum, commonly called Shasta daisy, is a hybrid developed by Luther Burbank (1849-1926) in the 1890s near snow covered Mt. Shasta in northern California. This hybrid typically features 3” diameter single flower heads with classic white rays and yellow center disks on rigid stems that generally do not require staking. The genus name comes from the Greek for white flower, referencing the conspicuous blooms of the Leucanthemum × superbum ‘Alaska’.

Tolerances

• Rabbit
• Deer
• Drought
• Dry Soil

Potential Problems

Leucanthemums generally exhibit some susceptibility to fungal issues, including leaf spots and stem rots, especially when humidity is high or air circulation is poor. Verticillium wilt is another concern in contaminated soils. Aphids, leaf miners, and mites can occasionally pose damage, though usually not severe enough to warrant aggressive chemical intervention. Good gardening practice, such as ensuring adequate spacing and avoiding overhead watering late in the day, helps mitigate most fungal risks.

Frequently Asked Questions

What hardiness zones is Shasta daisy suitable for?

Leucanthemum × superbum ‘Alaska’ thrives in USDA Hardiness Zones 5 through 9, offering reliable perennial performance across these temperate regions.

How large does Shasta daisy grow?

This cultivar typically reaches a height between 1.5 and 3 feet tall, with a spread ranging from 1.5 to 2 feet wide, offering substantial, but manageable, garden presence.

When does Leucanthemum × superbum ‘Alaska’ bloom?

Expect the classic daisy display of white flowers with yellow centers to appear reliably from July through August.

What sun exposure does Leucanthemum × superbum ‘Alaska’ need?

This plant demands full sun exposure to maximize flowering potential, although brief periods of light shade are tolerated in the hottest summer zones.

Conclusion

The Shasta daisy, specifically the Leucanthemum × superbum ‘Alaska’ cultivar, remains a champion for providing cheerful, low-effort summer structure and brightness in perennial beds. Its excellent cut flower capability and resistance to common pests like deer make it an extremely practical choice. Before planting, confirm your location falls within USDA Zones 5-9 and ensure you provide direct, full sun exposure for the best performance.

Companion Planting

Selecting appropriate neighbors is key to maximizing the health and aesthetic appeal of your Shasta daisies. Companion plants should share the need for full sun and moderately dry, well-drained soil. Consider integrating plants that bloom earlier or later than the Leucanthemum × superbum ‘Alaska’ to ensure continuous border interest into the fall.

Good neighbors include perennial Salvias, Russian Sage (Perovskia), and ornamental alliums that die back before competing for light. Plants with fine or contrasting foliage texture, like certain decorative grasses, help highlight the bold, coarse texture of the Shasta daisy leaves.

Propagation Tips

The primary and most effective method for propagating Leucanthemum × superbum ‘Alaska’ is division. Since these plants are somewhat short-lived, dividing clumps every 2 to 3 years is recommended maintenance practice to keep them vigorous and blooming strongly. Perform this division in early spring just as new growth emerges, or in early fall.

When dividing, carefully dig up the entire clump and gently separate the root ball into smaller sections, ensuring each new division has a healthy cluster of roots and shoots. Replant these divisions promptly at the same depth they were growing previously and water well to help them reestablish before the heat of summer arrives.