Tomas Pocius, no rights reserved (CC0) · iNaturalist
Crambe spp.
sea kale
Europe, Mediterranean, Africa, and central Asia
Overview
Crambe spp. is a genus of around 20 to 35 species of robust herbs in the cabbage family (Brassicaceae), found across Europe, the Mediterranean, Africa, and central Asia. The genus includes the edible coastal C. maritima, sea kale, and the ornamental C. cordifolia, giant kale or colewort. Plants form a basal mound of large, coarse, lobed or heart-shaped leaves, often grey-green and waxy, from which rises a much-branched flowering stem. Across the genus, foliage clumps stand 1 to 3 feet (30 to 90 cm) high, while the airy flower stems reach 2 to 8 feet (0.6 to 2.4 m) tall and spread 2 to 5 feet (0.6 to 1.5 m). In early summer the stems carry vast clouds of small, four-petalled white flowers, lightly honey-scented, that hover above the leaves like baby's breath. Flat or rounded seed pods follow. Plants grow on freely draining, often sandy or limy soils in full sun and tolerate coastal salt and drought, though the large leaves can be eaten by cabbage-family pests. The crowns are long-lived but dislike wet winter ground.
Native Range
Native to Europe, the Mediterranean region, Africa, and central and western Asia, on coastal shingle, steppe, and open rocky ground.Suggested Uses
Grown as bold structural plants in borders and gravel gardens, where the flower clouds give an airy contrast to solid foliage; C. maritima is also grown as an edible coastal vegetable. Suited to coastal, Mediterranean, and naturalistic plantings.How to Identify
Appearance
Size & Dimensions
Height2' - 8'
Width/Spread2' - 5'
Bloom Information
Flowering occurs in early summer, mainly June into July, when branched stems lift a haze of small white flowers above the foliage. The flowers are lightly honey-scented and draw bees. Seed pods develop as the bloom fades.
Detailed Descriptions
Foliage Description
Grey-greenGrowing Conditions
Sun Requirements
Requires 6-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Plants grow in full sun on deep, freely draining soils, including sandy and limy ground, with pH from 6.0 to 7.8. Water needs are low to medium once established, and plants tolerate coastal salt and summer drought. Wet winter soils rot the crowns. Hardiness spans roughly USDA zones 5 to 9. The crowns are long-lived but resent disturbance, so plants are left in place once settled.Pruning
Flowering stems are cut down after bloom unless seed is wanted. Tattered outer leaves are removed through the season. In C. maritima, shoots are sometimes blanched under cover in spring for eating.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
summer