How to grow sea kale

Sea kale plants are great in the British weather, with large attractive leaves and tasty stems that are a bit like asparagus.

Sea kale’s increasing in popularity as a home-grown crop and as it’s relatively easy to produce, and difficult to buy elsewhere, growing your own makes perfect sense!

What is sea kale?

Coming from the brassica family, sea kale’s technical name is Crambe Maritime, and it’s also known as sea cabbage.

It’s an ornamental plant with scented flowers and silvery leaves and now it’s sought after for its delicious stems.

It takes two years to fully establish for the best harvest.

Preparing soil for sea kale

Liking shelter from strong winds, sea kale is quite versatile and can cope with poor soil and some partial shade, although it thrives in sunshine and fertile, deep and well-drained soil.

How to plant sea kale thongs

Sea kale arrives as root cuttings called thongs.

  • If thongs arrive quite dry, they can be soaked in tepid water for a couple of hours.
  • Sea kale is best planted out from May onwards, when the soil’s warmer.
  • If needed, thongs can be planted in compost containers in spring, covered in 1inch (2.5cm) of soil, with regular watering to promote indoor growth before planting out in May.
  • When planting, thongs must have the pointed end downwards.
  • Keep thongs 2ft (60cm) apart in soil rows and planted 1inch (2.5cm) below the soil.
  • Use horticultural fleece as protection if snails and slugs are a problem.

When to harvest sea kale

Sea kale must be left until the second spring after planting, removing weeds from the soil during this time. Keep watered and add fish-based nutrients.

When the second spring arrives, the shoots can be cut to deliver the succulent stems you’ve been waiting for.