The plantains in my area do well in full sun or only partial sun, but not in heavy shade.
I’ve tried growing plantain it it never takes off. I get seeds from parks.
Same with mallow. I transplant it from parks and buy seeds. This is the first year I have seen a little Mallow plants pop up in the pens and I think I figured out that rodents eat it down to the ground when it gets big enough.
It’s crazy how excited I get when I see weeds growing!