Basically, the older and larger a turnip is, the more bitter it will taste. Choose ones that are around the size of a tennis ball for the best flavor. When it comes to actually cooking them, the trick to a non-bitter turnip dish is how you boil them.
Technically, rutabaga is actually a direct cross between cabbage and turnips, and it shares turnips’ slightly bitter flavor. Raw rutabaga tastes milder than turnips though, almost like a carrot without sweetness. It’s crisp, juicy, and just a tiny bit piquant. In cooked dishes, though, that’s where rutabagas shine.