I have made a habit of contacting my local nurseries to ask what their policies are re purchasing stock. I have been pleased to find the owner of my go-to nursery is a beekeeper, and is therefore more aware of and implements safe buying tactics. My other go-to (where my son works) is also very cautious about suppliers and does not use any chemicals at the nursery. I don't buy plants from big boxes, but have also asked them questions when plant browsing while shopping for building materials and they are generally clueless about just about everything. I think it is helpful to at least attempt to raise awareness by requesting information about their suppliers, and ask that the clerk pass on concerns to their managers. Who knows what happens with that...but it's worth a whirl. Every little bit helps.
