Organic curly kale. Organically grown seedlings of curly kale (Brassica oleracea var. acephala). Curly kale is a member of the cabbage family. It is a robust crop that is easy to grow. The name refers to its distinctive curly leaves. It is a nutritious food, with high levels of vitamin C and calcium. Organic farming avoids the use of most synthetic fertilisers, insecticides and herbicides, as well as genetically modified organisms. Photographed on Damhead Organic Farm, Scotland.