Sea kale
Crambe maritima · Brassicaceae
📷 Siim at et.wikipedia · CC BY-SA 2.5
The gardener's calendar
Ideal time to plant sea kale: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Scientific name
- Crambe maritima
- Family
- Brassicaceae
- Plant type
- Perennial herbaceous
- Foliage
- Deciduous
- Flowering
- May to June
- Mature height
- 80 cm
- Exposure
- Full sun
- Hardiness
- Hardy (zones 4-9)
- Origin
- Atlantic and Mediterranean coasts of Europe
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability medium.
Expert tips
The key tip
Sea kale produces long taproot systems: plant in deep soil (minimum 50 cm), mulch 5 cm to protect the crown. Young leaves (April-May) are harvested boiled or steamed, flowering stems like broccoli.
The common mistake
Harvesting too aggressively in the first year: this weakens the bulb.
The pro's trick
After flowering (June), cut stems at the base: this forces production of secondary leaves that are harvested in July-August, extending the culinary season.
Care
Exposure
Sea kale thrives in full sun, with at least 6 hours per day. A coastal or windy exposure doesn't bother it; it's naturally acclimated there. Avoid shade, which would reduce vigor and leaf production.
Watering
Keep the soil regularly moist but not waterlogged, especially during the first year of establishment. Once established, it will tolerate dry periods better thanks to its deep root system. By the coast, natural salt spray reduces watering needs.
Soil
Prefer well-drained soil, slightly sandy or gravelly, as the plant fears waterlogging. It tolerates poor soils and even slightly saline ones. An organic matter amendment at planting will encourage rooting.
Fertilizing
A moderate application of balanced fertilizer in spring is enough. Avoid excess nitrogen, which would favor foliage at the expense of flowering. Brassicaceae appreciate sporadic potassium applications.
Pruning and maintenance
Remove yellowed or damaged leaves as seasons progress. After flowering, prune lightly to encourage branching. Cleaning before winter prevents pest infestations.
Diseases and pests
Watch for flea beetles and slugs, common pests of Brassicaceae. Good drainage reduces root rot risks. Good air circulation limits fungal diseases.
Did you know?
Sea kale was long harvested wild from European coastal cliffs for its young shoots, considered a delicacy during the Renaissance. This excessive harvesting nearly caused it to disappear in the wild, hence the current interest in growing it in the garden. Its Latin name 'maritima' highlights its inseparable link with the coastal and saline environment.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
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Tips generated and checked by Viridia — adapt them to your local climate.