Local & seasonal, kale is produced in the UK almost all year long. This green brassica owns its popularity to being known as a superfood, rich in vitamins, minerals and nutrients. Because it deteriorates quickly you should not leave kale in the fridge for too long. It is at its best when the leaves are a deep vibrant green. The central ribs can be tough so discard them before cooking. You can then chop or shred the leaves. UK Season: September to April.