The species you listed above roseum elgans is pretty common in MA and do fairly well in both zone 5 and 6. I use to live in zone 6, just outside of Boston and now I am more northwest and in zone 5, and my rhodies have done well in both of these zones.

English Roseum and Nova Zembla are the two varities I grow now, but they do take a long time to get to the height where they would provide privacy for you.

Have you ever thought about Aborvitaes? They create a great privacy screen and if you purchase them at about 5 feet, they should grow faster than the Rhodys. They will also provide privacy in summer and winter, just like the rhodies will. It's all a matter of what you prefer.

Linda

Thanks, Linda!

The problem with arbor vitae, from what I have been told, is they need more sun to thrive. I am considering pyramidal yews for the same reason....they tell me they need less sun.

PJM is hardy & very popular here (5a). I have Pohjola's Daughter, but it is a slow grower. There are a bunch developed by the University of Helsinki that should be reliable for you.

You could try Rhododendron Maximum - That's supposed to be one of the hardiest, and it's certainly one of the largest Rhodos. It can bloom in full shade, although it grows a bit leggy.

I've got a 'Boursault' rhododendron that seems to have done fairly well so far - It's a Catawba hybrid, so it should be fairly hardy.