Hello, Steve. Zone 6 requires that you plant early blooming Winter Series camellias developed by the U. S. National Arboretum or the late blooming April Series developed by Camellia Forest Nursery. Many of those are good in Zone 6.

Rhodies and camellias like some protection from the hot afternoon summer sun. Shade starting at around lunch time or so would work well for either plant but, in some places near the Canadian border, you can grow rhodies in near full sun conditions.

Do you mind me asking in what state do you live? There are some Zone 6s where the soil is a problem for rhodies. They like well draining, well mulched, acidic soils and have very tiny shallow roots in the top 4" of the soil that do not do well growing in soils with limestone. For example, Colorado can be difficult for rhodies. The alternatives in such cases are to try building raised beds using acidic soil or try growing them in pots.

The link below will take you to the American Rhododendron Society's Search Page. You can choose plants using various parameters such as height, zone temperatures, color, etc.

Luis

Here is a link that might be useful: Rhododendron Search

Luis--

Thanks for the link, that will come in handy. My town is zoned 7a; but because my front yard is an exposed slope that gets strong winter winds from both north and south, some plants that grow well in more sheltered locations don't make it for me. I think I'm at least a half-zone lower than my neighbors.

My soil is mostly neutral to slightly-alkaline stony clay, and the beds I have put in are all heavily amended. This year I've been more diligent at mulching well and watering regularly, and haven't lost a single plant, and I'd like to keep up that record. My concern with the rhododendrons was they might resent strong morning sun in the winter the same way the camellias did--they burned something terrible, and languished until I moved them to the north side of the house. Now, they've taken off...even some that were down to practically bare twigs. (And they're all from Camellia Forest...that place is like a gardener's mecca.)

"neutral to slightly-alkaline stony clay" is essentially anti-rhododendron. :)

Rhododendrons and azaleas prefer soils with a pH of 4.5 to 6.0, soils that are acidic, retain moisture while not remaining soggy, are high in organic content....so loose and rich.

I suspect you would have the same problems with rhododendrons on your east facing slope as you did with the camellias -

"Eastern exposures are generally successful and particularly so where mornings are often overcast. In the eastern US however, early morning sun in winter can damage frozen leaves and flower buds by thawing them too rapidly. If cold climate gardeners provide some early morning shelter (especially for the early blooming types), an eastern exposure can be satisfactory."

Some rhododendron flourish is sunny conditions. My house faces the south and I use all iron clads on that side. They love it. They tend to be more compact and bloom more. Some of the better hardy sun loving varieties are:

A. Bedford-nice blotched flower
Anah Kruschke-reddish purple
Belle Heller-white with yellow blotch
Boule de Neige-hardy white, excellent foliage
Cadis-pink
Chionoides-hardy white
County of York-white
Cunningham's White-white tolerated less acidic soils
Cynthia-rosy red
Fastuosum Flore Pleno-lavender blue
Gomer Waterer-pinky white, very sun tolerant
Landmark-purple red
Nova Zembla-hardy red
Olga Mezitt-pink
PJM-lavender pink, very hardy
Roseum Elegans-hardy rosy-lilac
Solidarity
Trilby-red
WestonÂs Aglo-pink
Wissahickon-bright rose
Wyandanch Pink-vivid pink