Don't go to them, you have no proof that you tried to stop it. Write them a letter that says:
On _____I spoke with ______ and asked that you not hand out business cards with my home phone number on them. (It's your old fax number) This request was disregarded. My attorney said to mail you this letter and thereby making my request for you to stop handing out business cards, receipts, shopping bags or anything else with my personal phone number on them a formal request. I will be keeping a copy for my own records in case there is a need for future litigation.
Sign it, date it, and mail it so that it has to be signed for. That should do it. Or you could just answer you phone and say, "We don't want your business, try __________ " and give them the name of another nursery. LOL