Sea kale

Crambe maritima. Sea kale is a perennial vegetable, hardy to zone 4, in the brassica family. It is tolerant to salt, so a great choice if you live on the coastline or near a road. The whole plant is edible - spring shoots are eaten like asparagus, the leaves can be used like kale, and the flower buds can be used like broccoli. Apparently, even the roots are eaten raw or cooked! And the flowers are, of course, a bee magnet.