How to plant and care for Sea Kale

Crambe maritima

🥕 Vegetable 🔁 Perennial

A handsome, blue-leaved coastal perennial whose blanched spring shoots are a gourmet treat, eaten like asparagus. Lives for years.

At a glance: harvest in March.

When to plant and care for it

JanFebMarAprMayJunJulAugSepOctNovDec

Plant

Harvest

Timed for a typical UK garden (last frost mid-April). The app uses your own town's frost dates.

Mid March – mid April · 4 weeks before the last spring frost
Plant Crowns
Plant crowns 45 cm apart in well-prepared, weed-free ground enriched with compost. Plant root cuttings ("thongs") upright with the top just below the surface. Do not harvest in the first year.
0–1 days after “Plant Crowns” · Mid March
Water In
Water well and keep moist while they establish.
14–21 days after “Water In” · Late March – early April
Mulch
Mulch with well-rotted manure or compost to hold moisture and smother weeds.

January
Cover to Blanch
Clear dead leaves and cover each crown with an upturned bucket or forcing pot to blanch the new shoots.
Starts from year 2.
March
Cut Blanched Shoots
Cut the pale shoots at 15–20 cm, then remove the cover so the plant can recover. Take a photo!
Starts from year 2.
April
Feed and Mulch
Scatter a general feed and mulch with compost or seaweed.
June
Remove Flower Stems
Cut off flower stems so the energy goes into the crown.
November
Autumn Tidy
Clear the dead leaves once they collapse.