Frozen herbs will get you through the winter. I’ve done that with plantain before. I have no idea what the actual shelf life would be long term. I’ve never seen any studies. I also have no idea what the shelf life of a frozen salve bars would be though I’m sure it’d be fine short term.
There are lots and lots of other things I have no idea about…but I have no idea what they are. :0)
Don't use herbs or combine herbs with medications or use them during lactation or pregnancy without talking with your healthcare provider.