Collard greens
Collard greens (or collards) are loose leafed cultivars of Brassica oleracea. Collard greens are part of the acephala group of the species, which includes kale and spring greens.
Collard greens are known for their large, dark colored and edible leaves. They are also known as a garden ornamental.
Collard greens are available year round. They are tastier and more nutritious in cold months, after the first frost.
References
Leaf vegetables
Brassica oleracea