I am probably in the same position as you, with little space in the coop and four hens. I have food and water outside for when I let them out in the morning. To not attract rats etc at night, I have the food in a bin with a drainpipe in its side (where the hens access the food) with a screwtop...
Buddleia, or butterfly bushes, grow quite fast and the flowers look a bit like skinny lilac. Butterflies are attracted to them. They can be cut back and will regrow again quite quickly. They grow on very poor soil too.
I am retired in France and am new to chickens (and postings!). Have last year adopted a couple of red barnyard hens with health problems - a steep learning curve involving lots of research! Have added two silkie chicks to the flock this year. Really enjoying things, until now when I discovered...