Growing Carpet of Snow Alyssum in Pots

Carpet of snow alyssum (Lobularia maritima ‘Carpet of Snow’) is a gorgeous variety of sweet alyssum that forms a dense, trailing mound of delicate white blooms. With its sweet honey-like fragrance and frost-tolerant nature, carpet of snow alyssum is an excellent choice for container gardening. In this comprehensive guide, we’ll walk through everything you need to know about successfully growing this beautiful plant in pots.

An Overview of Carpet of Snow Alyssum

Carpet of snow alyssum is a compact, low-growing variety of sweet alyssum that only reaches about 4-6 inches in height but spreads 12-24 inches wide It produces masses of tiny, fragrant white flowers on short stalks over deep green foliage. The blooms have four petals and form in rounded clusters

This variety is prized for its long blooming period, extending from early spring to first frost in fall. Deadheading spent blooms regularly encourages continuous flowering. The tiny white blooms also make this variety perfect as a “filler” in mixed containers.

Carpet of snow alyssum thrives in full sun to partial shade exposure. It tolerates drought once established but prefers consistently moist (not soggy) soil. This variety is also quite cold hardy tolerating frost and freezing temps once established.

Choosing the Right Container

Carpet of snow alyssum isn’t too picky when it comes to containers. Focus on choosing a container with good drainage. You can plant it alone in a medium sized (10-12 inches wide) container or mix it with other trailing plants like ivy in a larger mixed planter.

Terra cotta, plastic, concrete, wood and other materials all work well. Make sure the container has drainage holes at the bottom to prevent soggy soil. For hanging baskets, opt for a wire basket lined with moss or coconut coir rather than solid plastic which doesn’t breathe.

Best Soil for Containers

Use a high quality commercial potting mix, not garden soil, for your containers. The potting mix will be lightweight and drain well. You can also create your own mix by combining equal parts peat moss, perlite or vermiculite, and compost. This DIY mix will be fertile and retain some moisture while still draining excess water.

Before planting, work some slow release fertilizer into the top few inches of the potting mix according to package directions. This will provide nutrients for the alyssum’s initial growth.

Planting Carpet of Snow Alyssum in Containers

Carpet of snow alyssum can be planted either from seed or young starter plants. For quicker results, use young plants from your local nursery. Spring is the best time to plant them in your region.

To plant, first moisten the potting mix thoroughly. Dig a hole just larger than the root ball of your young plant. Very gently loosen any tangled or circling roots before placing the plant in the hole.

Fill in soil around the root ball leaving just a bit of space (about 0.5 inch) between the soil surface and the base of the plant. This will help prevent crown rot. Tamp down the soil gently and water thoroughly until it drains from the container’s base.

Caring for Container Grown Plants

Carpet of snow alyssum isn’t too demanding in terms of care but does require some attention to thrive:

• Sunlight: Full sun to partial shade exposure. At least 6 hours of direct sun per day is best. Move container to follow the sun’s shifting path.

• Water: Keep soil consistently moist but not soggy wet. Water whenever top 1 inch becomes dry. Increase frequency during summer heat.

• Temperature: Prefers cool temps below 75°F. Can tolerate light frosts when established. Move containers to a sheltered spot during hard freezes.

• Fertilizer: Apply liquid fertilizer like fish emulsion every 2-3 weeks during the active growing season.

• Pruning & Deadheading: Prune lightly in early spring to shape. Deadhead spent blooms regularly to encourage continuous flowering.

Overwintering Containers

In cold winter regions, carpet of snow alyssum generally won’t survive winter outdoors in containers unless extremely well protected. You have a few options for overwintering:

• Move containers to an unheated garage or porch. Water very sparingly, just 1-2 times/month.

• Bring containers indoors to a sunny window. Prune back leggy growth by 1/2 to encourage bushiness.

• Take cuttings in late summer/fall, root indoors, and overwinter plants inside to replace outdoor containers next year.

• Allow outdoor plants to die back in winter then replace with new plants in spring.

If you keep plants growing indoors over winter, transition them gradually back outdoors in spring once night temps stay above 40°F to avoid shock.

Common Problems and Solutions

Carpet of snow alyssum is relatively trouble-free but may encounter a few potential issues:

• Leggy growth: Plants become stretched out and straggly. Make sure they get full sun. Prune back leggy stems by 1/3.

• Root rot: Stems collapse, leaves wilt and turn yellow. Check for soggy soil and improve drainage. Allow plants to dry out between waterings.

• Aphids: Small soft-bodied insects that feed on new growth. Knock them off with a strong spray of water or apply insecticidal soap.

• Mildew: White powdery coating on leaves. Improve air circulation and avoid wet foliage. Apply neem oil or sulfur fungicide.

Tips for Maximizing Blooms

With proper care, carpet of snow alyssum will flower non-stop from spring through fall. Here are some extra tips for maximizing blooms:

• Choose a sunny location and avoid moving containers once plants are established.

• Apply fertilizer every 2-3 weeks during spring and summer. Phosphorus promotes blooms.

• Prune lightly in early spring to remove dead material and shape plants.

• Deadhead spent blooms frequently by pinching them off. This encourages continuous reblooming.

• Watch for pests like aphids that can weaken plants and reduce flowering.

Enjoying Carpet of Snow Alyssum Year After Year

With its cascading white blooms and sweet fragrance, carpet of snow alyssum is one of the most delightful options for container plantings. Follow this guide to get your plants established successfully in pots and keep them thriving year after year. A bit of routine care will keep this lovely plant flowering from spring until frost.