For me, the color purple is one of the most important colors in a medicinal garden. We are told by nutritional “experts” to “eat the rainbow” to ensure that you eat many of the phytonutrients that plants provide for us. The different colors reflect the different chemicals that plants synthesize to ward off disease. Eating a wide variety of these phytochemicals is one of my core dietary principles. Today, I want to emphasize that some of the most important phytonutrients are found in purple-colored plants.
It’s fairly unusual for a plant to be purple; historically, the color purple was often found in plants that were highly poisonous. Two examples are the deadly Aconite plant and Belladonna, otherwise known as deadly nightshade. Both are well known homeopathic medicines precisely because they produce very potent poisonous substances. As Shakespeare once said, “Let poison by your physic” (“physic” is an Old English word for “medicine”). The point is that the color purple is often associated with very active biological substances that, in correct doses, can act as therapeutic substances for both the plant and animals ingesting the plant.
Throughout the thousands of years that humans have been selecting and breeding plants, purple ones were cultivated. Examples include the purple fruits of the eggplant, purple leaves of tree collards and the purple-colored long beans of the traditional Asian diet. Each of these plants is rich in the flavonoids and anthocyanins associated with the color purple, which have been shown to reduce inflammation and protect DNA.
In recent times, as research on these disease-fighting substances has exploded, plant breeders are working to intensify and select for the color purple. Some examples I have growing in our Napa garden include purple cauliflower, purple broccoli, purple mizuna (a usually green Asian vegetable), purple peppers (which would make it even harder to say “pick a peck of purple pickled peppers”), and even purple sweet corn. The principle is that rather than eating just white cauliflower, we can choose a more nutrient-dense and therefore therapeutic version. It’s easy to do, the plants are beautiful, and they add color, flavor and interest to your garden.
At Dr. Cowan’s Garden, we are always looking for ways to add more nutrients to our vegetable powders. One of the ways we can do this is to source purple kale for our Kale Powder in addition to the usual green kale. As time goes on, and a wider variety of vegetables becomes available to us, we will continue our pursuit of “The Color Purple.”
Tom Cowan, M.D.