How to Grow Alyssum (Sweet Alyssum): Fragrant Carpets of Color

Sweet Alyssum (Lobularia maritima) is a low-growing, honey-scented annual that forms billowing mounds of tiny white, pink, lavender, or purple flowers. Perfect for edging, rock gardens, containers, and pollinator borders, it blooms from spring to frost with minimal care. Its delicate fragrance attracts beneficial insects, making it a functional beauty.

Quick Start Guide

Aspect	Details
Botanical Name	Lobularia maritima (syn. Alyssum maritimum)
Family	Brassicaceae
Type	Annual (short-lived perennial in zones 9–11)
Height/Spread	4–8" tall, 10–12" wide
Bloom	Spring to frost
Colors	White, pink, rose, lavender, purple, apricot
Fragrance	Sweet, honey-like
Light	Full sun to part shade
Soil	Average, well-drained
Water	Moderate; drought-tolerant once established
Deer Resistant	Yes

Growing from Seed

Indoors (4–6 weeks before last frost)

1. Sow in seed-starting mix; press seeds onto surface (light aids germination).
2. Keep at 65–70°F (18–21°C); germinates in 7–14 days.
3. Provide bright light; harden off before transplanting.

Direct Sow (After last frost)

1. Prepare weed-free, loose soil.
2. Scatter seeds; press lightly; do not cover.
3. Water gently; keep moist until emergence.
4. Thin to 6–8" apart.

Care & Maintenance

• Water: Regular until established; then weekly deep watering. Avoid overhead watering to prevent fungal issues.
• Fertilize: Light feeder. Balanced slow-release at planting; optional liquid feed monthly.
• Shearing: If plants become leggy or bloom slows in heat, shear back by 1/3–1/2. Water and feed for quick rebound.
• Deadheading: Not required—self-cleaning—but shearing serves same purpose.
• Heat: May pause blooming in intense summer heat; resumes in cooler fall.

Design Uses

• Edging: Define beds, paths, rose borders.
• Rock Gardens: Spills over stones; softens edges.
• Containers & Hanging Baskets: "Spiller" element; pairs with upright annuals.
• Pollinator Borders: Attracts hoverflies, parasitic wasps, bees—natural pest control.
• Underplanting: Beneath roses, shrubs, tulips (hides fading bulb foliage).
• Vegetable Garden: Insectary plant; attracts beneficials to control aphids.

Popular Series

• 'Carpet of Snow': Classic white, uniform.
• 'Easter Bonnet': Mix of pink, rose, lavender, white.
• 'Wonderland': Compact, early, heat-tolerant.
• 'Snow Crystals': Larger flowers, tetraploid vigor.
• 'Clear Crystals': Single colors (purple, pink, white); no white eye.

Troubleshooting

• Leggy, Few Flowers: Too much shade, heat, or nitrogen. Shear back; ensure sun.
• Yellow Leaves: Overwatering, poor drainage. Improve soil; water less.
• Downy Mildew: Yellow patches, white fuzz underside. Space for air flow; water at base; remove affected.
• Aphids: Blast with water; insecticidal soap if needed.

Sweet Alyssum is the ultimate "plant it and forget it" annual—fragrant, pollinator-friendly, and endlessly versatile. A few packs of seed yield months of delicate beauty.