How do you keep free range chickens out of a flower bed?

I recommend putting up a fence. You can even put up a temporary one with stakes and chicken wire. Here is an article that might help as well - http://backyardchickenproject.com/how-to-keep-chickens-out-of-the-garden/

actually they're probably doing you a favor by consuming bugs and caterpillars that will eat more of your plants than they do -- but a low, unobtrusive fence will work ...

check out what Joanne Gaines did with her chicken coop and plants. She had a perfect solution!

Both of my grandmother's flowerbeds were always surrounded by low wire fencing to keep out the chickens.

Great advice!

I had this same problem in with my veggie garden so I fenced off the space then they jumped the fence. So then I went with a covered raised concept and it worked great. May be a possible solution with a few tweaks for your space.

https://www.gardenupgreen.com/2014/10/growing-successfully-in-covered-raised.html