Tag Archives: yam

Sweet Potato Awareness Month

November is Sweet Potato Awareness Month (SPAM), and I do my part by reminding people that yams are something else entirely. As a foodie and an evolutionary biologist, I feel obliged to be a nudge about this. So here are three images to help.

First, a photograph of a white yam (Ipomoea rotunda) in a bin of sweet potatoes.

Colin Purrington Photography: Blog photos &emdash; A white yam (Dioscorea rotundata) in a bin of sweet potatoes (Ipomoea batatas)

Second, a photograph of three cultivars of sweet potato (all Ipomoea batatas) next to a yellow yam (Dioscorea cayennensis).

Photograph of sweet potatoes and yam

Third, an illustration of how yams and sweet potato are related (they aren’t). As a bonus, I’ve also indicated the position of potato.


Please share this page with your family prior to Thanksgiving dinner. It will be one less thing to bicker about. If you need more details, here’s my “Yams versus sweet potatoes” page. Read it if you want to know why the slave trade caused the whole “yam” confusion problem.

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Minor victory in my war against yam labeling fraud

In my futile quest to convince people that sweet potatoes shouldn’t be called yams (which are unrelated plants), I discovered that one can actually report vendors who label sweet potatoes as yams. So, for giggles, I reported Giant Foods to the USDA’s Misbranding and Misrepresentation Office. Below is a photograph I took in November of their organic sweet potatoes:

giant-sweet-potato-05 (1)

And now in all of their stores (that I’ve checked), they sell sweet potatoes labeled as sweet potatoes:

Nature's Promise sweet potato at Giant

It might be a small victory, but Giant Foods is giant, so I’m pleased. If you want to know more about my futile war, please see my page on Yams versus Sweet Potatoes. If you want to make your own report, just visit the above USDA site and send the contact person a photograph of the label along with store contact information. They’ll do the rest, and apparently in a persuasive way.

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Open letter to produce managers re: yams

Dear Produce Manager,

If you want to sell more orange-fleshed sweet potatoes, craft your labels with “yams” in parentheses, like this:

Sweet potatoes (“yams”)

Because you are a produce manager, you undoubtedly know that a yam is a completely unrelated thing, so using quotation marks will indicate to ignorant shoppers that you are not actually selling yams. As you also surely know, “yam” is regional slang used by some (generally older folks) to refer to a sweet potato that has orange flesh. But if you only have “yams” on label, some shoppers might get flustered and leave for another store that labels sweet potatoes as “sweet potatoes.” Still others are looking for a specific variety of orange-fleshed sweet potato (Beauregard, Jewel, etc.), so list that, too. E.g.,

‘Beauregard’ sweet potatoes (“yams”)

That’s a lot of text, but different varieties are good for different recipes, and some of your customers are over-educated foodies who care deeply about such details. Ideally, cut one in half and cover in plastic wrap to convince skeptical shoppers that it does, indeed, have orange flesh.

Colin Purrington

These are sweet potatoes

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