Porto Rico is an old variety out of LSU. It has been tinkered with by a lot of folks since. The original is a vining plant, red potato with orange flesh. Moist flesh that drips sugar when baked. What we old folks call honey drippers. Someone developed a short vine version (bunch) probably in the thirties. Less difficult to control but flavor is the same, for my taste one of the best bakers ever. It is more susceptible to diseases than modern varieties. For that reason I currently grow Carolina Ruby which similar in flavor. The others are most probably a locally developed , or possibly renamed variety, Mutations are not rare in sweet potatoes.
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