Overview

Crithmum maritimum is a bushy herbaceous perennial in the genus Crithmum, part of the Apiaceae family, with evergreen foliage. It typically grows around 0.1-0.5 metres tall and 0.1-0.5 metres wide, reaching full size in around 5-10 years. Crithmum maritimum grows best in full sun, and tolerates most soils and any pH. Its UK hardiness is rated H6. It is attractive to pollinators. Suggested uses include coastal, cottage and informal garden, gravel garden and wildlife gardens.

About

Crithmum maritimum, also referred to as rock samphire or sea fennel, is a perennial plant that typically grows up to 40 cm tall. From April to September, it produces clusters of greenish-yellow flowers. This species features succulent foliage with triangular-shaped leaves in cross-section.

About the genus

Crithmum comprises low-growing annuals or perennials that typically attain a height of approximately 30 cm. These plants feature woody stems and fleshy, dissected leaves, producing flowers that range from white to greenish-yellow. Species in this genus are commonly utilized for their ability to trail or serve as ground cover.

Growing conditions

Best soil and position for Crithmum

Sunlight
Full sun
Soil type
Chalk, Loam, Sand
Soil pH
Acid, Alkaline, Neutral
Soil moisture
Well-drained
Aspect
East-facing, North-facing, South-facing, West-facing
Exposure
Exposed, Sheltered
UK hardiness
H6

Plant details

Crithmum maritimum size, habit and characteristics

Plant type
Herbaceous Perennial
Habit
Bushy
Foliage
Evergreen
Height
0.1-0.5 metres
Spread
0.1-0.5 metres
Time to full height
5-10 years
Suggested uses
Coastal, Cottage and informal garden, Gravel garden, Wildlife gardens

Care notes

Pruning and caring for Crithmum maritimum

Cultivation
Naturally occurs in coastal grassland, and rocky cliff places
Pruning
No pruning required
Propagation
Propagate by seed sown in autumn
Pest resistance
Generally pest-free
Disease resistance
Generally disease-free

Frequently asked questions

How do I grow Crithmum maritimum?

Naturally occurs in coastal grassland, and rocky cliff places.

Where is the best place to plant Crithmum maritimum?

Crithmum maritimum prefers full sun. It suits exposed and sheltered positions.

What soil does Crithmum maritimum need?

Crithmum maritimum is adaptable and grows happily in most soil types, including chalk, loam and sand. It is happy in soil of any pH. Aim for soil that stays well-drained.

How do I prune Crithmum maritimum?

No pruning required.

How big does Crithmum maritimum grow?

Crithmum maritimum reaches a height of 0.1-0.5 metres and a spread of 0.1-0.5 metres. It takes around 5-10 years to reach full size.

Is Crithmum maritimum hardy in the UK?

Crithmum maritimum has a UK hardiness rating of H6.

How do I propagate Crithmum maritimum?

Propagate by seed sown in autumn.

Is Crithmum maritimum good for pollinators?

Yes — Crithmum maritimum attracts and supports pollinators such as bees and other beneficial insects.