I have two Vitex trees and they are honey bee magnets. I had an email advertisement from this company, in my inbox today, offering Vitex trees. They are hardy. One tree is growing in the worst clay soil you can imagine. I highly recommend this tree to beekeepers. Last winter my location dropped below -20F. and I did see a little die back. I am seeing buds now. My Vitex typically starts blooming about the 3rd week of June.
I have purchased other live plants from this business and they have done well. Strictly Medicinal Seeds can be a good source for the hard to find but good nectar/pollen sources.
https://strictlymedicinalseeds.com/product/nirgundi-vitex-negundo-tree/Several years ago an Asian family knocked on my door asking if they could take some of the foliage to make a poultice with for the mother. I was happy to oblige but very curious about how it was used and was it successful.