Written by Melissa Hurley
Have you ever wondered, what is the difference in a sweet potato and a yam and all the different colors? And which one exactly is a yam?
Although orange-fleshed sweet potatoes have traditionally been referred to as yams in parts of the United States and Canada, they are not part of the same family and therefore they are not yams.
Sweet Potatoes – so many!
Diane/Garnet: red skin/orange flesh
Covington/Beauregard: orange skin/orange flesh
O’Henry/Golden Sweet: yellow skin/white flesh
Kotobuki/Murasaki: purple skin/white flesh
Stokes Purple: purple skin/purple flesh
True yams are cultivated in Africa, Asia, Latin America, the Caribbean and Oceania and not traditionally in the United States or Canada. The yam is a starchy, drier, edible root of the Dioscorea genus. It is rough and scaly and very low in beta carotene. They are related to lilies, and can be as small as a regular potato or ridiculously jumbo in size (some grow five feet long!). Yams have a cylindrical shape with blackish or brown, bark-like skin and white, purple or reddish flesh. True yams can be tough to find. They aren’t carried in many local grocery stores, so your best chances of finding them are in international and specialty markets.
Now you know. You’ve been probably eating sweet potatoes and calling them yams. Go forth and educate others. Keep it clear: sweet potatoes are not a type of yam and yams are not a type of sweet potato. They are both tuberous root vegetables that come from a flowering plant but they are not related and actually don’t even have a lot in common.