How to Grow Sweet Alyssum
Lobularia maritima
Sweet alyssum is one of the easiest and most rewarding annuals you can grow. Scatter seed directly where you want it from March onwards — it germinates in a week and flowers within two months. The honey-scented white, pink, or purple flowers attract hoverflies and beneficial insects all summer. It makes a perfect edging plant, container filler, or path-side carpet. Shear back by half in midsummer if it gets leggy and it will bounce back with fresh flowers. It self-seeds freely in mild areas, so you may never need to buy seed again.
When to Start
Direct sow outdoors as soon as soil reaches 10°C — typically early to mid spring. Can also be started indoors 4 weeks earlier for a head start.
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Growth Stages
Approximate days from start
Care Essentials
- Light feeding only. A single application of balanced fertilizer at planting time is sufficient. Too much feed produces foliage at the expense of flowers.
- Sweet alyssum is one of the easiest annuals to grow from seed. It is honey-scented, attracts hoverflies and other beneficial insects, and makes a superb edging plant or gap-filler. It self-seeds freely in mild areas, returning year after year without replanting. Sow direct from March onwards or start indoors earlier. It tolerates poor soil and light frost, making it one of the first and last annuals to flower.
Growing Conditions
- Sow indoors
- —
- Transplant out
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- First harvest
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Spacing & Planting
| Plant spacing | 20 cm |
| Row spacing | null cm |
| Mature height | 15 cm |
| Mature spread | 30 cm |
Space 15-25 cm apart. They spread quickly and knit together to form a fragrant carpet. Excellent for edging and filling gaps.
Pests & Diseases
Pest Flea Beetle
Identification: Tiny round holes in leaves, as if peppered with shot. Small shiny black beetles that jump when disturbed.
- Water well to keep plants growing strongly through damage
- Cover young plants with fleece until established
- Rarely needed — healthy plants outgrow the damage
Pest Slugs and Snails
Identification: Seedlings eaten to ground level; slime trails
- Apply ferric phosphate slug pellets around seedlings
- Ferric phosphate-based pellets
Disease Downy Mildew
Symptoms: Yellowing leaves with greyish-white fuzzy growth on undersides. Plants may become stunted.
Treatment: Remove and destroy affected plants. Improve air circulation.
Prevention: Avoid overcrowding. Water at soil level. Ensure good drainage.
Disease White Rust (White Blister) Albugo candida
Symptoms: White, shiny, blister-like pustules on leaf undersides. Upper leaf surface may show yellow spots.
Treatment: Remove and destroy affected leaves. Improve air circulation.
Prevention: Avoid overhead watering. Space plants well.
Frequently Asked Questions
- How far apart should I plant Sweet Alyssum?
- Plant Sweet Alyssum 20cm apart with nullcm between rows.
- When does Sweet Alyssum flower?
- Sweet Alyssum typically flowers approximately 30 days after transplanting.
- Is Sweet Alyssum frost hardy?
- Sweet Alyssum is classified as Hardy.
