Sweet Alyssum (Lobularia maritima) ‘Snow Crystals’

Lobularia maritima 'Snow Crystals'

‘Snow Crystals’ is a vigorous white sweet alyssum noted for extra‑large blooms and staying power. Plants form mounds that are taller than standard alyssum and cover quickly. Blooms carry a strong honey fragrance and attract many small pollinators. Flowering is long in cool weather and rebounds after a trim if heat slows the display. This selection is widely used in containers and at the front of borders for a bold white carpet.

At‑a‑glance

  • Group/Class: sweet alyssum seed cultivar
  • Height × spread: 6 to 10 in (15 to 25 cm) × 12 to 18 in (30 to 45 cm)
  • Bloom window: late spring to frost in cool conditions
  • Color & flower form: white; larger clusters of tiny four‑petaled flowers
  • Fragrance: 3 strong
  • USDA hardiness: grown as annual in most of North America
  • Breeder / Year / Origin: unknown
  • Awards/registration: Missouri Botanical Garden Plant of Merit
  • Pet safety: safe

How it differs

  • Larger flowers than typical sweet alyssum strains.
  • Better heat and wind tolerance than many traditional selections.
  • Mounding habit that can reach medium edging height.
  • Long season with quick recovery after shearing.

Strengths

  • Recognized as a Plant of Merit for dependable performance.
  • Strong fragrance and abundant bloom.
  • Useful where a more substantial alyssum mound is desired.
  • Works in mixed containers and massed borders.

Care in one minute

  • Choose full sun in cool‑summer areas or light afternoon shade in hot regions.
  • Plant in well‑drained soil that is average in fertility and neutral to slightly alkaline (6.0 to 8.0).
  • Water regularly during establishment and in prolonged dry spells; allow the surface to dry between waterings.
  • Feed lightly at planting; too much nitrogen reduces bloom.
  • Shear or deadhead after the first flush to prompt rebloom and keep plants compact.
  • Treat as annual in most of North America; remove before winter or allow limited self‑seeding.

Watch‑outs

  • Flowering can stall in high heat; cut back and water to encourage rebloom.
  • Seedlings are susceptible to damping‑off in overly wet media.
  • Can self‑sow; remove spent plants if reseeding is not desired.

Best uses (tags)

containers; borders; edging; pollinators; rock gardens

Provenance note

‘Snow Crystals’ has been cited for greater heat and wind tolerance and received the Missouri Botanical Garden Plant of Merit designation in 2000.

References

Written by: Your Flowers Guide editorial team
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