Cabbage and Carrots in winter

I've become something of a produce connoisseur but with no formal training, so I don't have the vocabulary or a lot of information to go along with it, just experience.   Here's something curious I've learned.  We are lucky to get locally grown cabbage and carrots throughout most of our winter.  They are grown from local CSAs and stored properly.  Well, they seem to get sweeter as winter goes on.  I think they are sweetening as they age.  It's sort of like fruit, they sweeten and then eventually are too old and rot.  I think they are at their sweet spot right now.   My salads have been really tasty thanks to the cabbage, and I am eating lots of carrots because they are so good.   I think the season for both will end in a month or so, so I am going to enjoy them this month.