The term collard has been used to include many non-heading Brassica oleracea crops. While American collards are best placed in the Viridis crop group, the Acephala cultivar group is also used ("without a head" in Greek) referring to a lack of close-knit core of leaves (a "head") like cabbage does, making collards more tolerant of high humidity levels and less susceptible to fungal diseases.The plant is a biennial where winter frost occurs; some varieties may be perennial in warmer regions. It has an upright stalk, often growing over two feet tall. In Portugal more than 50% of the vegetables eaten everyday North of the Tagus river in all sort of receipts include this "couve" and almost every single peasant's home with one patch of land has them all year long.
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