I planted a pot of curly leaf parsley, or thought I did until it came up as broccoli

Those seed packets look so similar
Regarding your garlic though, how much have you planted? As it's in a bath, I presume the soil is potting compost or similar and thus pretty loose, so you should be able to pull the garlic through gently with little disturbance to the carrots. You may have to pull a carrot or two as well but it shouldn't be too bad, should it?
I've planted rows of Tagetes between my carrot this year and when I'm weeding I keep brushing the Tagetes so the stink is enough to make my eyes water and will hopefully fool those little carrot fly blighters. Go on, someone tell me that Tagetes and carrots don't get on.
