Ah you're already on the Antos train! ^^ I buy them by the box, for the dog's and the hams.
Well that's refreshing to hear, I wish our local vets knew a bit more about such things.
(sorry for stealing the light but.. ;D) you can give clover - red, white and the grass kind. And as for herbs you can give most of those you'll find in the super market, e.g. mint, basil, parsley ect. Aside from clover and dandelion, I wouldn't go exploring too much in the garden. There are many harmful plants you may come across, such as buttercup - big no no.
They can eat chamomile flowers, but you're probably going to have to buy them from somewhere and they aren't all that common in pet shops and such.