Gardening Flowers Annuals Sweet Alyssum This low-growing plant blooms like crazy during mild spring and fall temperatures. By Viveka Neveln Viveka Neveln Instagram Viveka Neveln is the Garden Editor at BHG and a degreed horticulturist with broad gardening expertise earned over 3+ decades of practice and study. She has more than 20 years of experience writing and editing for both print and digital media. Learn about BHG's Editorial Process Updated on July 30, 2022 Share Tweet Pin Email Colorful Combinations Alyssum flowers are most often found in a crisp, clean white. However, sometimes you'll see deep purple, light pink, or even soft peachy-hued varieties. The abundant white blooms make this plant easy to use in garden designs because they go with everything. Put them at the bases of plants to cover the ground and draw even more pollinators to your garden. Sweet alyssum is also valuable for its early spring blooms when nothing else has taken off. Sweet Alyssum Care Must-Knows Alyssums are easy plants to start from seed. Because they're cool-season annuals, they can be sown directly in your garden a few weeks before the last frost date for your area. They don't mind the cold, as long as it isn't a hard freeze. If you want an even quicker impact in your garden, start seeds indoors 5-6 weeks before the last frost date. It is best to plant alyssum in well-drained soil, keeping plants evenly moist throughout the season. Winter Flowers for the South Be sure your alyssums get plenty of sunshine. In northern climates with mild summers, full sun is ideal, allowing plants to keep blooming as much as possible. In areas where summers are warmer, plant alyssums in part shade, especially to protect them from the hot afternoon sun. This helps extend your bloom time a little longer. If the season does get too hot and plants stop blooming, shear plants back by about half. This will encourage new growth and give your plants a good base to bloom once cool weather returns in fall. Because alyssum is a cool-season annual, plants will generally stop blooming to conserve energy in the summer. However, some varieties are much more tolerant of the heat and will give you more bloom time. In most cases, those with darker-colored blossoms tend to have less heat resistance than the pure white varieties. New Innovations Because alyssum is a cool-season annual, plants will generally stop blooming to conserve energy in the summer. However, some varieties are much more tolerant of the heat and will give you more bloom time. In most cases, those with darker-colored blossoms tend to have less heat resistance than the pure white varieties. More Varieties of Sweet Alyssum Sweet Alyssum Overview Genus Name Lobularia maritima Common Name Sweet Alyssum Plant Type Annual Light Part Sun, Sun Height 6 to 6 inches Width null to 12 inches Flower Color Pink, Purple, White Foliage Color Blue/Green Season Features Fall Bloom, Spring Bloom, Summer Bloom Special Features Fragrance, Good for Containers, Low Maintenance Zones 10, 11, 9 Propagation Seed, Stem Cuttings Problem Solvers Groundcover 'Clear Crystal Lavender' sweet alyssum Justin Hancock Lobularia maritima 'Clear Crystal Lavender Shades' is an extra-vigorous selection with fragrant, larger-than-typical lavender blooms. It grows 10 inches tall and 14 inches wide. 'Easter Bonnet' sweet alyssum Peter Krumhardt Lobularia maritima 'Easter Bonnet Pastel Mix' offers soft pink, lavender, and white blooms on tidy 4-inch-tall plants. 'Frosty Knight' sweet alyssum Justin Hanccock Lobularia 'Frosty Knight' is a novel variety with cream-edged green leaves as an added bonus to the bountiful white blooms. 'Snow Crystals' sweet alyssum Peter Krumhardt Lobularia maritima 'Snow Crystals' has fragrant, extra-large flowers on vigorous plants. 'Snow Princess' sweet alyssum Justin Hancock Lobularia maritima 'Snow Princess' is an exceptionally vigorous variety that's heat tolerant and bears clusters of white flowers much larger than older varieties. It's very fragrant, as well, and grows 6 inches tall but can trail to 5 feet. Sweet Alyssum Companion Plants Nemesia Peter Krumhardt Nemesia is a charming cool-season annual with pretty little snapdragon-shaped flowers—often fragrant—that bloom in a wide range of colors. It does best in spring and fall (and winter in mild-winter climates), though some varieties have better heat tolerance than others. In cool-summer areas, such as the Pacific Northwest, nemesia will continue to bloom right through the summer into fall. Nemesia prefers moist, well-drained soil that's rich in organic matter. Pansy Peter Krumhardt From tiny, cheerful Johnny jump-ups to the stunning 3-inch blooms of Majestic Giant pansies, the genus Viola has a spectacular array of delightful plants for the spring garden. They're must-haves to celebrate the first days of spring since they don't mind cold weather and can even take a little snow and ice. They're pretty planted in masses in the ground but also appreciated for the early color they bring to pots, window boxes, and other containers. By summer, pansies bloom less, and their foliage starts to brown. When that happens, you'll have to be tough and tear them out and replant warm-season annuals, such as marigolds or petunias. But that's part of their charm as an ephemeral celebration of spring. Stock Julie Maris Semarco Stock offers a wonderfully spicy, distinctive scent. Plant it in spring several weeks before your region's last frost date; this annual thrives in cool temperatures and stops blooming once hot weather arrives. It's especially wonderful in window boxes and planters at nose level, where its subtle effect can best be appreciated. Stock is slightly spirelike and comes in a wide range of colors. It makes an excellent cut flower, perfuming bouquets. It grows best in full sun or part shade and moist, well-drained soil. Garden Plans for Sweet Alyssum Small-Space Vegetable Garden Plan Peter Krumhardt Here's how to add great looks—and tastes—to your landscape with an easy small vegetable garden plan. Download this garden plan. Drought-Tolerant Garden Plan Peter Krumhardt This informal mixed garden bed features drought-tolerant trees, evergreen shrubs, perennials, and annuals. Click here to get this plan. Low-Water Garden Plan Janet Loughrey No matter where you live, it's inevitable that plants will take defeats in the middle of July. Count on this easy-care garden to stay looking good through dry spells. Get this garden plan now. Was this page helpful? Thanks for your feedback! Tell us why! Other Submit