Are soft root vegetables edible? I bought some parsnips two days ago. Today they are slightly soft. Are they safe to use? (The goal is a mashed root dish, so unless there's a safety issue the softness shouldn't matter.)
Yes. If they're not mouldy, rotting, or unpleasant-smelling, carrots, parsnips etc. are safe even quite floppy. When parsnips go bad you often get very soft brown areas that grow quite fast - avoid.

Mashing or stewing root veg that's past its best texture is a good way to use it up.