I have a plant app but it doesn't seem correct
It's not viney but that would be awesome if it were Clematis
I think it is a member of the mint family. Probably deposited by a bird.
Chocolate mint dors not smell minty until you pour hot water over the leaves for tea.
Did you have Dahlias planted there last year? They might have survived the winter.
No it was only veggies
Do you have a Rose of Sharon nearby? Might be seedlings.
No but I do see the leaves resemblence