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How to Grow Alyssum and Attract Pollinators

Sweet alyssum is one of the most enduring garden annuals—and for good reason! This charming plant adds soft drifts of color, attracts important pollinators, and helps manage garden pests. Here are my top tips for growing alyssum, plus a few additional pointers to ensure success.

1. Plant Alyssum From Seeds or Transplants

Starting from seeds:

• Growing from seeds gives you more varieties to choose from. A few of my favorite types include: Allure Pastel Blend, Oriental Nights, Rosie O’Day, and Tiny Tim. 
• Direct sow: Lightly sprinkle a seed or two every 6 inches. Press them gently into the soil without burying; they need light to germinate.
• Water: Keep seeds moist (a light mist works well) until they germinate—often in just 2–3 days under ideal conditions.
• Thinning: Once seedlings reach 2–3 inches tall, thin them to 6–12 inches apart, depending on the variety.

If you want to start a few other flowers alongside alyssum, here are 10 easy cool-season flowers to plant from seed.

Indoor seed-starting (optional):

• Early jump: For an even earlier start, plant seeds indoors about 6–8 weeks before your last frost date.
• Light requirement: Press seeds onto the surface of a seed-starting mix, and keep them lightly moist and warm.
• Hardening off: Before moving seedlings outdoors, spend 7–10 days gradually introducing them to outdoor conditions.

Learn more: How to Start Seeds Indoors

Using transplants:

• Look for compact growth: Overgrown transplants may struggle when planted out.
• Spacing: Again, space them about 6–12 inches apart.
• Water well: Don’t let newly planted transplants dry out; consistent moisture helps them establish quickly.

Looking for more fall color that grows as easily as alyssum? Check out 10 easy-to-grow fall flowers.

2. Choose the Best Location for Planting Alyssum

Alyssum typically grows about 3–9 inches tall and can spread 6–12 inches wide. It’s a low-lying plant perfect for the edges of beds, lining pathways, filling hanging baskets, and more.

• Sunlight: Alyssum performs best with at least 6 hours of direct sun. In very hot climates, some afternoon shade can help extend bloom time.
• Soil pH and quality: While not fussy, alyssum prefers well-draining soil. Slightly alkaline to neutral pH (around 6.0–7.5) is ideal. Heavy clay soils can lead to rot; improve drainage by adding compost or planting in raised beds.
• Containers: Alyssum also grows beautifully in pots or hanging baskets—just be prepared to water more frequently.

3. Plant Alyssum at the Right Time

Sweet alyssum is a cool-season flower. It thrives in moderate temperatures and may slow down or die back during hot summer months.

• Cold-winter areas: Start seeds indoors from late winter to early spring (if you like). Transplant or direct-sow outside after the last frost. Most varieties bloom through fall if weather cooperates.
• Mild-winter areas (Zones 7–10): You can often grow alyssum year-round, though it may not bloom vigorously in the peak of summer heat. In places like the low desert of Arizona, plant seeds or transplants in fall through early spring for the best display. (October through March)
• Square Foot Gardening: If you’re using a square foot garden layout, allow about one square foot per plant. This spacing can vary based on the variety’s mature size.

4. Use Sweet Alyssum to Attract Beneficial Insects

Alyssum isn’t just pretty—it’s also a powerful ally against aphids. Its tiny flowers provide ideal nectar for syrphid (hover) flies, whose larvae feed on aphids, plus a host of other beneficial insects like lady beetles and parasitic wasps.

One reason I plant sweet alyssum everywhere is that it helps attract the beneficial insects that manage pests like aphids. Learn more in How to Get Rid of Aphids.

• Companion planting: Place alyssum near roses, lettuce, brassicas, or any plant prone to aphids. Watch as beneficial insects arrive to help keep pests in check. Learn about more plants that attract beneficial insects in this guide.
• Living mulch: In vegetable or ornamental beds, a “carpet” of alyssum can act as living mulch, suppressing weeds while adding color and attracting pollinators.

Want more ideas to pair with alyssum this season? See my guide to best companion plants for cool-season gardens.

5. Care for Alyssum as It Grows

Alyssum is generally low-maintenance, but a little TLC goes a long way to ensure continuous blooms.

• Watering: Alyssum likes regular water but dislikes soggy soil. In containers, especially hanging baskets, keep an eye on moisture levels since they dry out faster. Learn more about the best way to water containers here.
• Fertilizer: They’re not heavy feeders, but a balanced, slow-release fertilizer at planting can support robust growth. If plants seem tired mid-season, give a light boost with a liquid organic fertilizer every few weeks. I generally feed with compost and worm castings at the beginning of the season and then don’t feed again.
• Deadheading and pruning: Although deadheading isn’t strictly necessary, trimming plants back by about half after the first big flush of blooms often encourages a second wave of blossoms. Prune lightly to maintain shape and fullness.

Hot weather tip: Do not prune back if daytime temperatures are getting hot. This will kill the plant.

• Overwinter care: In milder climates, alyssum can survive winter. It may get leggy, so a trim or replanting each season might be preferred. If a hard freeze is likely, protect or replace as needed.
• Self-seeding: Many alyssum varieties drop seeds and come back the following season. Let some spent flowers remain if you’d like volunteers the next year.

Dealing With Pests and Diseases

• Root and stem rot: This can develop in waterlogged soils. Plant in well-drained locations or raised beds and avoid overwatering.
• Common pests: Alyssum is relatively pest-free, but if you do see slugs or snails, use simple barriers like copper tape or pick them off at dusk. Beneficial insects usually take care of aphids, so long as you’re avoiding broad-spectrum insecticides.

Additional Tips and Final Thoughts

• Seed Saving: You can collect seeds from dried blooms at the end of the season. Store them in a cool, dry place for next year’s planting—or let nature do its thing and enjoy self-seeded volunteers.
• Fragrance: Alyssum’s honey-like scent is an extra little treat for the senses, especially as the plants grow larger.
• Favorite Plant Pairings: I love tucking alyssum around roses, adding color and a natural pest-deterrent strategy. It’s also fantastic interplanted with lettuce or along garden paths.

Need help choosing what else to plant with alyssum in the low desert? Browse Arizona annual flowers: a visual guide for low-desert gardens.

By following these tips, you’ll create a garden bursting with color and buzzing with beneficial insects. Sweet alyssum’s easy-going nature, quick germination, and pollinator benefits make it a winning choice for both new and experienced gardeners. Plant some seeds or transplants, give them the right conditions, and enjoy the sea of blossoms (and grateful pollinators!) in the seasons to come.