Crambe maritime Perennial Vegetable Zone 4I have been raising this vegetable for nearly 10 years. It is simply one of the best perennial vegetables you can grow, right up there with asparagus and rhubarb. It is considered a perennial kale and can be used in much the same way. Traditionally the young spring growth is blanched by covering for a couple of weeks before harvesting. This is supposed to make the plant more tender and palatable. I do not believe this is necessary, and the blanching process will eliminate much of the nutrients. We eat the spring leaves and shoots raw, mixed into salads, or they can be lightly steamed or sauteed. The raw flavor is stronger than regular kale, but still quite delicious. The leaves and stalks are also much thicker and juicier than kale. As the weather warms the plant will develop flower buds which can be picked and steamed like broccoli. Seacale flowers are quite impressive and aromatic. They will attract a large number of beneficial insects including honey bees. In the fall you can again harvest the smaller more tender leaves until the plant dies back. I mulch my plants with straw for winter protection. Seacale likes well-drained soil. It will grow in partial shade to full sun. Propagation is by division or seed. I start my seeds indoors 8-10 weeks before setting out in the spring. It is a good idea to remove the shell surrounding the seed before planting. Space 2′ apart in beds or rows.