Lobularia maritima 'Royal Carpet'
‘Royal Carpet’ is a classic purple‑flowered sweet alyssum grown from seed. It forms a very low mat that edges paths and fills containers. The honey fragrance is strong and steady in cool weather. Flowering peaks in spring and fall and may pause in midsummer heat. Gardeners use it to contrast with white selections such as ‘Carpet of Snow’. The strain is easy to start and is suitable for quick seasonal color.
At‑a‑glance
- Group/Class: sweet alyssum seed cultivar
- Height × spread: 2 to 6 in (5 to 15 cm) × 10 to 12 in (25 to 30 cm)
- Bloom window: spring to frost in cool conditions
- Color & flower form: rich purple to violet; tight 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: All‑America Selections Flower Winner 1953
- Pet safety: safe
How it differs
- Lower profile and deep purple color compared with white strains.
- Strong perfume similar to species but color holds better in cool weather.
- Quick to flower from seed for edging and small containers.
Strengths
- Verified award history for performance.
- Dense, even carpet effect at the border edge.
- Pollinator friendly in spring and fall.
- Simple culture from direct sowing.
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)
edging; containers; borders; pollinators; rock gardens
Provenance note
‘Royal Carpet’ is an early seed strain recognized by All‑America Selections in 1953 for garden performance and color.
References
- All‑America Selections – Alyssum ‘Royal Carpet’ Winner (1953)
- Missouri Botanical Garden – Lobularia maritima species profile
- ASPCA – Alyssum non‑toxic listing
Written by: Your Flowers Guide editorial team
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