I’m not sure how to rotate foliage beforehand but what I do know is that the rotation of foliage is paired to the object it is attached to (so if you rotate the wall then the foliage should rotate with it). I haven’t really used the foliage system all that much myself but you might be able to change the rotation of the actual assets or their direction when they are originally placed (unfortunately I don’t think they can be altered separately after being placed).