I have several purple vegetables and herbs growing in my garden this summer.
Botanically, purple plants are fascinating to me. We all learn in science class that plants get their green color from the chlorophyll in their leaves, which is used in photosynthesis to make food. Actually, plants have three color pigments: chlorophyll (green) carotenoid (red), and anthocyanin (blue). Various combinations of these pigments give plants their different colors. Carotenoid pigments give carrots their orange color, while anthocyanin pigments appear in purple grapes – and in my purple herbs and vegetables.
Purple vegetables are a more recent novelty. As a kid we had purple eggplant and cabbage, but not purple green beans, cauliflower, carrots, and potatoes. Today there are many options. Sometimes entire plants are purple, while other times it's only the edible plant part. Purple plants are becoming increasingly popular for added color in salads and cooked dishes.
We are eating the plant's leaves of cabbage and basil. Thus their all of their plant parts are solid or variegated shades of purple. Cabbage comes in various shades of green, as well as red or purple types. Easy varieties for homeowners to raise include 'Red Meteor' (75 days to harvest; firm; good for all seasons) and 'Ruby Ball' (71 days; slow to burst; resists both cold and heat). I plan to ferment sauerkraut with the cabbage from my garden.
Numerous varieties of purple basil are available including 'Ararat' (mottled green and purple); 'Dark Opal,' 'Osmin Purple'; 'Red Rubin'; and 'Purple Ruffles.' Purple basil makes great flavored vinegar.
In cauliflower, we eat the purple flowers. 'Violet Queen' is deep purple with open broccoli-like heads, and 'Graffiti' has brilliant purple heads. Both look great on a veggie tray.
It's the plant's fruit that we eat in peppers and green beans. Unfortunately, the purple color of these vegetables fades to green during cooking. According to Sandy Mason, Illinois Master Gardener Coordinator, to retain as much nutrition and color, add a little lemon juice or vinegar to the vegetables during cooking to produce a prettier final product, and don't overcook them.
To me, the oddest and most interesting of all are edible roots, such as purple carrots and potatoes.
Maybe next year I'll plan better and devote an entire area to purple vegetables and herbs. I can even envision a magical world there, where Prince sends purple rain down to water and nourish my fantasyland in purple.