Blue, violet and indigo foods have tons of antioxidants, Some blue and purple fruits and vegetables are also really high in vitamin C. Anything in this category will help improve circulation and prevent blood clots, so they are great for the heart and can help prevent heart disease. They are also known to help memory function and urinary tract health and to reduce free radicals.
Purple cauliflower is actually a type of broccoli that is purple and turns green upon cooking. It packs the same pigments, called anthocyanins (antioxidant flavonoids) that give blueberries their gorgeous hue. Cauliflower is one of the most concentrated sources of vitamin C among cruciferous vegetables. Cruciferous vegetables can help your body get rid of the toxins that can damage cells and increase the risk of cancer.
Fiesoles are special baby artichokes with a rich purple color. They're grown in California, taste rich and nutty and are almost entirely edible because they have no choke inside. Cooking reduces their vibrant hue so I eat them raw (shaved in a salad).