Kapral Scotch Kale is very easy to grow and as a winter crop is hard to beat being very hardy and unproblematic to grow. 
Can survive to -12 below freezing, even pigeons will leave it alone.
It is a medium early variety with dark green leaves which are heavily blistered and very curly.
Highly resistant to frost, it produces an abundance of tender and tasty delicate leaves. Ideal for exposed situations and it is also very resistant to frost.