Sea Kale

Herbaceous

Sea Kale

Crambe maritima

Also known as: Seakale, Sea Colewort

HerbaceousGround Cover Brassicaceae EdibleGround CoverErosion ControlOrnamentalDynamic Accumulator
Hardiness Zone
4-9
Ideal Temp
35–75°F
Survives Down To
-20°F
Life Cycle
Perennial

Sea kale (Crambe maritima) is a perennial brassica of European and Black Sea coasts, forming a basal rosette of thick, waxy blue-green leaves and summer clouds of white four-petaled flowers on branching stems to about 2–3 feet. Plants spread slowly by rhizomes and resemble a wild cabbage adapted to sand, salt spray, and poor fertility; blanched spring shoots (“sea kale chicory” style) are a traditional crop. ☀️💧 Sun and Water Requirements: - Full sun with excellent drainage; tolerates light coastal salinity. - Regular water in fast-draining soil; hates summer waterlogging. In subtropical and tropical Americas lowland tropics it is a cool-season or maritime-trial crop—grow during the coolest months in raised gritty beds, or accept dormancy during intense heat. ✂️ Methods to Propagate: - Root cuttings: take thick root pieces in winter, bury horizontally in sand, keep moist until shoots appear. - Seeds: sow fresh; plants take a few years to reach full cropping size. 🌾 When to Harvest: - Mound plants in late winter to blanch tender shoots in early spring; harvest leaves young for cooking like kale. Avoid stripping all foliage from first-year plants.

Good Neighbors
  • Saltbush
  • Lavender
  • Yarrow
Known Threats — Organic Solutions Only
Aphids
Aphidoidea
Cabbage Aphid
Brevicoryne brassicae
Cabbage Looper
Trichoplusia ni
Cabbage Root Fly
Delia radicum
Cabbage Root Maggots
Delia radicum
Cabbage Worms
Pieris rapae
Cross-striped Cabbageworm
Evergestis rimosalis
Diamondback Moth
Plutella xylostella
Flea Beetles
Alticini
Harlequin Bug
Murgantia histrionica
Imported Cabbageworm
Pieris rapae
Swede Midge
Contarinia nasturtii