Sweet Alyssum Care Guide: How to Grow Sweet Alyssum

Sweet alyssum (Lobularia maritima), also known as alyssum, is a species of low-growing plants that is part of the mustard family. This Mediterranean native plant originated as a wildflower on coastlines and is drought-tolerant. Sweet alyssum has a sweet smell similar to honey that attracts bees, butterflies, hummingbirds, and other pollinators. It is a fast-growing plant that blooms white, pink, red, violet, yellow, and lilac flower clusters and has narrow green leaves.

Sweet alyssum grows best in cooler temperatures, so it will bloom in the spring, fade in the summer, and re-bloom again in the fall. It is typically grown as an annual, but will survive as a perennial in warmer climates.

Sweet alyssum plants reach three to six inches in height and grow in both mounding and trailing configurations. Sweet alyssum can be decorative or functional in your garden. Use it:

1. 1. In hanging baskets: Sweet alyssum will trail when planted in hanging baskets or window boxes.
2. 2. As a filler plant: Plant sweet alyssum as filler for nooks and crannies in garden walkways or rock gardens.
3. 3. As a groundcover: Plant sweet alyssum as groundcover beneath and around new plants to shade the area and inhibit weed growth. Sweet alyssum is a natural mulch when grown in a garden bed under taller plants.
4. 4. As a pollinator plant: The sweet smell of the plant will attract pollinators to your garden.

Sweet alyssum may have originated as a wildflower, but it has now been cultivated in an array of colors with longer bloom times.

1. 1. ‘Snow Crystal’: This cultivar is heat-tolerant and features tiny white flowers. It is also a taller variety that can grow up to 10 inches tall.
2. 2. ‘Snow Princess’: This cultivar has large white flowers and tends to sprawl, with some branches growing as long as 24 inches. It is also cold- and heat-tolerant, and it blooms in the summer. This cultivar is sterile, so it does not produce seeds and can only be grown from cuttings.
3. 3. ‘Clear Crystal’: This cultivar comes in white and lavender varieties.
4. 4. ‘Rosie O’Day’: These blooms come in various shades of pink.
5. 5. ‘Pastel Carpet’: True to its name, this variety comes in pastel shades of apricot, pink, violet, blue, white, and yellow.

Sweet alyssum is a fast-growing plant that will bloom and proliferate within two months of seeding. Follow these tips to add sweet alyssum to your garden:

• Sow the seeds before the last frost. Start alyssum seeds indoors several weeks before the last frost date, and transplant outdoors once the seedlings are sturdy. Or, plant the seeds outdoors in spring when the danger of frost is past.
• Give the plants room to grow. Ensure there are six to 12 inches between the plants to avoid overcrowding.
• Plant the seeds in full sun or partial shade. Sunlight will help the seeds germinate, so keep them uncovered.
• Plant the seeds in well-draining soil. Keep the soil moist until the seeds germinate—about 7 to 20 days after planting. If you are starting the seeds indoors, transfer the seedlings outdoors after germination.

After sweet alyssum blooms, the plants do not require much attention. Follow these tips to keep your alyssum healthy season to season:

• Keep sweet alyssum in full sun. The plants do best in full sun but can also survive in partial shade. Make sure your sweet alyssum gets at least 6 hours of sunlight each day.
• Water sweet alyssum sparingly. Give the plants one inch of water per week and make sure the soil dries out completely between waterings. Soggy soil will contribute to root rot or leaf blight.
• Deadhead the plants to encourage growth. Deadheading the spent flowers will help the plant continue to bloom. The plant can re-seed and self-sow quickly, so while it may look like sweet alyssum is constantly blooming, it’s likely new growth flowering.

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