The type of purple and blue potatoes my wife and I have been enjoying from our CSA this year were hard to remove with just a normal brush. It was quite the predicament – we do enjoy eating potatoes with the skins on, but in order to remove the hard dirt spots, we thought we needed to peel the entire potato.
An idea that I came across was using a butter knife. You can use either side of the knife, YMMV, so try both of them, depending on what type of potato problem you have.
As shown above – there were potatoes of 2 different colors. Pictured on right is the end result – dirt scratched off. And on the leftis the starting point – little bubbly dirt appearances.
Get cleanin’ and enjoy your food!