Last year I planted 3 kinds of potatoes. When I harvested them each variety...
Last year I planted 3 kinds of potatoes. When I harvested them each variety had small irregular cavities in the center. They were not soft or rotten and the rest of the potato was firm and perfectly normal. we just cut out the affected area and the rest was good. I have never seen this before in any of the potatoes I have grown.
Hubbard County Minnesota potatoes
Here are a couple of links that describe various potato problems:
I hope this is helpful. Please contact AaE again if you have further questions.