Contrary to popular belief, whether it’s red, pink, green or something in-between, rhubarb’s color has nothing to do with ripeness. Rather, its hue is completely determined by genes; different varieties produce different colors, and green rhubarbs are just as sweet as red ones.
Green varieties actually tend to be better producers—growing faster and having bigger yields. But because consumers tend to favor bright red rhubarb, many contemporary growers take the yield hit and breed plants for color instead.
Red rhubarbs owe their ruby hue to anthocyanins—antioxidants that produce red, purple, and blue colors in plants and confer free-radical fighting health benefits. But if you’re gardening or foraging for your rhubarb, watch out for the leaves; they’re quite toxic!