Cruciferae flora flowers Greece Greek natural nature petals spring white wild Italy path track trail valley yellow brassica cabbage crop danish Denmark farm field landscape plant Samsø vegetable background texture black kale Cavolo nero crucifer England english garden Great Britain lacinato leaves plants vegetables agricultural clouds green kent November sky winter brassicaceae cabbages cultivars cultivation food greens grow Sussex varieties black dye hanging herb Isatis tinctoria pendulant purple seeds traditional Woad