Does it need deadheading?

You do not have to, but shearing it back by half after the first flush of blooms encourages a fresh wave of flowers.

Can it grow in shade?

It prefers full sun but will tolerate partial shade, though it may bloom less vigorously.

Plant guide

Sweet Alyssum.

Lobularia maritima

Pronounced lob-yoo-LAIR-ee-uh muh-RIT-ih-muh

Also known as Sweet Alison, Sweet Alyssum, Sweet-alice

Sweet alyssum is a charming, low growing plant known for its sweet, honey like fragrance. It creates a beautiful carpet of tiny flowers that look great in borders or containers. It is a favorite for attracting pollinators to the garden.

At a glance

Care level: Easy
Plant type: Annual
Light: Full sun to partial shade
Indoor light: direct
Water: Every 2 to 4 days
Mature size: 15 to 30 cm tall
Growth rate: fast
Hardiness: USDA 5 to 9
Bloom time: Spring through autumn

Care

Keep the soil consistently moist but not soggy to encourage continuous blooming. If the plant gets leggy or stops flowering, give it a light trim to promote a fresh flush of growth. Watch for aphids during warmer weather.

Watering: Keep the soil evenly moist to support the rapid growth and flowering cycle.
Feeding: Apply a balanced liquid fertilizer monthly to keep the blooms coming.
Pruning: Shear back by one third if the plant becomes straggly to encourage new flowers.
Repotting: Typically grown as an annual, so repotting is usually not necessary.
Soil: Well draining, fertile soil
Soil pH: 6.0 to 7.5
Temperature: 5 to 30°C
Humidity: 40 to 60%
Drought tolerance: moderate
Lifespan: Annual, or short lived perennial in frost free climates.
Fragrance: strong
Deer and rabbits: moderate

Signs it needs repotting

Roots growing out of the drainage holes.
Water running straight through the pot without soaking in.
Plant growth slowing down significantly during the growing season.

Safety

People: It is not considered toxic to humans.
Pets: This plant is generally considered non toxic to cats and dogs.
Children: There are no specific safety concerns for children, though the small flowers could be a minor choking hazard if ingested in large quantities.
Contact allergens: Some individuals may experience mild skin irritation if they handle the foliage frequently.
Airborne allergens: The pollen is generally not a significant allergen for most people.
Edibility: While the flowers are technically edible, they are often treated with pesticides in garden centers, so only eat those you have grown yourself without chemicals.

How to identify it

Tiny four petaled white flowers
Dense clusters of fragrant blooms
Narrow lance shaped grey green leaves
Low growing mat forming habit

Height: 0.1 to 0.3m
Spread: 0.2 to 0.4m
Leaves: grey-green, evergreen
Flowers: white, pink, purple, 0.5 to 1cm

Common problems

Aphids — Small insects that cluster on new growth and suck sap from the plant.
Downy mildew — A fungal issue that causes yellowing leaves and gray fuzzy growth in humid conditions.

Growing it

Propagation: seed
When to plant: spring, autumn
Overwintering: In areas with frost, it is usually treated as an annual and removed after the first hard freeze. In very mild climates, it may persist through winter if kept tidy.
In containers: It is excellent for containers and hanging baskets, requiring at least a 6 inch pot to thrive.

Seed Sowing

Scatter seeds on the soil surface in early spring.
Press them lightly into the soil but do not bury them as they need light to germinate.
Keep the soil consistently moist until seedlings appear in 1 to 2 weeks.

Plant it around the base of taller vegetables to act as a living mulch and attract predatory wasps that eat garden pests.

Grows well with

Petunia — They share similar water needs and create a lovely color contrast in containers.
Geranium — The mounding habit of geraniums pairs well with the trailing nature of sweet alyssum.

Keep away from

None notable — It is a very friendly companion plant that rarely interferes with others.

Similar species

Basket of Gold — It is a perennial relative that also features small yellow flowers and a low growing habit.

Science

Family: Brassicaceae
Genus: Lobularia
Order: Brassicales
Class: Magnoliopsida
Native range: Mediterranean region.
Conservation: It is not of conservation concern and is widely naturalized globally.

It thrives in sandy, well drained soils and often colonizes disturbed coastal sites.

Value to wildlife: nectar source, attracts beneficial insects
Pollinators: bees, butterflies, moths
Uses: ground cover, container filler, pollinator garden, rock garden

Through the year

JFMAMJJASOND

Flowering

Fruiting

Foliage

Ecological indicators

Light: 7/9
Moisture: 4/9
Salinity: 5/9
Soil reaction: 6/9
Temperature: 5/9
Nutrients: 4/9

Taxonomy resolved against GBIF.

Questions people ask

Does it need deadheading?: You do not have to, but shearing it back by half after the first flush of blooms encourages a fresh wave of flowers.
Can it grow in shade?: It prefers full sun but will tolerate partial shade, though it may bloom less vigorously.

Where the name comes from

Lobularia refers to the small lobes of the seed pods, while maritima reflects its natural habitat along coastal areas.

Good to know

It is a member of the mustard family.
The name Alyssum comes from Greek for curing madness, though it has no such medical use.
It is often used as a living mulch to suppress weeds.
It can bloom continuously from spring until the first hard frost.

Is your sweet alyssum looking unwell?

This page is a general guide. Pocket Botanist diagnoses problems from a photo of your actual plant, works out watering for your light and conditions, and reminds you when care is due.

Get the app

This guide was generated with AI and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.