Jolly Green Giant Tree Collard, Brassica oleracea (Acephala Group), is a fast-growing, perennial hybrid vegetable, related to kale and cabbage, known for producing large, nutritious leaves year-round, reaching several feet tall with minimal care, offering continuous harvests in USDA Zones 8-11, though it may need staking and is prone to pests like aphids. It's a vigorous, non-flowering variety (compared to others) that's excellent for continuous cutting, making it a favorite for gardeners wanting a low-maintenance, long-term leafy green source.