The OED makes no mention of an acronym. First cite is from 1845, which pretty much rules out an acronym: people did not coin words that way until WWII. (There is one exception: “hep”). Further, the OED makes no mention of any such society.
A more likely origin is that it derives for “spud,” meaning a digging tool. That dates back to 1667, and it’s possible that a spud was used to dig potatoes. The transfer from tool to vegetable would seem a simple step.
> The OED makes no mention of an acronym. First cite is from 1845, which pretty
> much rules out an acronym: people did not coin words that way until WWII.
> (There is one exception: “hep”). Further, the OED makes no mention of any
> such society.
Do you have a cite for “hep” coming from an acronym? That’s not what all the dictionaries I’ve checked say. Also, a better limit on the formation of acronyms is about 1910. There were some in World War I.