I have success with BST cats on Zizia. I have both types. Heart Leaf and regular. They will also use Queen Anne's Lace. I don't like Queen ann's lace but it has sprung up in my yard from brought in soil and is pretty common so easy to find if you need to put your cat on something else.
I have lots of Zizia,
I also have Rue (Ruta graveolens) for them
