my potatoes are bitter but not green
Last year we had many green potatoes in both our sharpes and colleen. This year after only half our potatoes were usable. We planted last year's green ones as seed and planted them deeper, at least 3/4 of a foot. I just uncovered the first of our new potatoes, skinned them and boiled them and STILL they taste bitter and acrid. I don't know what to do. Is it our soil? It's very heavy and lumpy - 2nd year soil (previously a field). Is there any way we can rescue the remaining crop? We live in Orkney, Scotland and everyone else doesn't seem to have a problem.
Some types of potatoes produce more solanin (the chemical that gives potatoes a bitter taste) than others. Possibly by replanting the green ones (the green areas have a high concentration of solanin) you have unknowingly encouraged solanin-producing potatoes. You can also try amending your soil to make a better texture. Here's an article that might help: https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/improving-garden-soil.htm
Perhaps you could get some tips from your neighbors.