Solanum tuberosum subsp.
andigean (tentative genus, species, and subspecies.)
The purple potato is a
tuber surrounded by
myth,
humor,
wariness and a rather distinct lack of readily available information online.
It is indeed purple, or even blue in some varieties, and usually with an even stronger hue on the inside, especially in the inner
medulla, or meat of the tuber.
I personally find purples much more flavorful and finely textured than the pithy
russet, and even the esteemed reds. The color does take some getting used to, but realize the purple hue is entirely natural, not unlike the potatos close relative,
Solanum melongena, or
eggplant. The intense coloration is also wonderful for creative cooking. Delicious purple potato chips are also available.
Like all potatoes, the purple descends from South America, namely
Peru,
Argentina, and
Ecuador. (The potato was introduced to Europe, and later Asia, via Spain approximately 1570.) The information I have from memory is that the purple primarily comes from Peru. I suspect that the purple is closer to the original ancestral tuber found in the wild before human cultivation and breeding.
Purple potatoes may be resistant to
blight and
pests.
Organic farmers are investigating using strains of heirloom or contemporary purple potatoes as a
fungicide,
herbicide, and
pesticide free method of growing
viable and
resistant crops. This may be due to naturally occuring
solanine acting as a natural defense. Certainly, the aerial plant and leafy greens of the tuber's above ground portion are toxic and should not be eaten.
If you can find them, try them. They are worth the extra cost, and usually I don't see them costing much more than a good Red or Rose Gold
baking potato. All of the purples I have seen have been organically produced, perhaps due to their natural resistance. The labeling of organic produce, of course, varies by location.
Sources:
http://www.uga.edu/vegetable/potato.html
http://www.sciencedaily.com/releases/2001/09/010918134619.htm
Personal Memory