Carrots usually arrive in shades of orange, purple, yellow, or white, so a green ring around the top can look like the vegetable has wandered into the wrong garden department. That green color usually comes from a simple culprit: light exposure. When the upper part of a developing carrot sits too close to the soil surface, sunlight can reach tissue that normally grows underground, encouraging chlorophyll production and creating a green shoulder or ring.
A green top rarely signals a serious problem. It does not mean the carrot has gone rotten, and it does not mean something poisonous has crept into the vegetable. The color does tell a useful story about how that carrot grew, though, and a few small changes in planting and hilling can keep the next crop looking much more like the familiar orange roots that inspired Bugs Bunny.
