agriculture beet cooking diet farming field food fresh gardening green harvest healthy kale leaf lettuce nutrition organic red salad summer vegetables fennel spring bitter chicory-family coloring colors colouring colours cook dichorium-intybus edible head herbaceous-plant Italian-chicory leafy-vegetable perennial plant produce radicchio raw red-chicory red-leaf-lettuce reddish-purple-leaves round salad-vegetable thin-leaves uncooked vegetable white-veined