I have Mexican sage and a native australian vine called Hardenbergia violacea growing unprotected in my run, they leave them alone. I also have a small mandarin orange tree in there that they have left completely alone, but when it started to bloom I put chicken wire around it to keep them from eating the buds. I put bricks around all plants to keep them from digging the roots. There is also english ivy in there that they leave alone but I didn't plant it. When they were younger they destroyed everything, now if it tastes bad they nibble a bit but mostly leave them alone.
All chickens are different, I'd try different things, especially deer resistant plants, protect them until they are established then see what happens.
All chickens are different, I'd try different things, especially deer resistant plants, protect them until they are established then see what happens.