Rhododendron kuisianum, the Kyushu azalea, is a low-growing Japanese species, only 18 inches high but is not hardy in Zone 5. Try Zone 7.

R. linearifolium 'Macrosepalum', the plant is 3 feet tall and the leaves are deciduous and 3 inches long. But the flowers are even more curiously shaped than those of the species; they have 1 1/4-inch-long sepals that overshadow the petals. The flowers of this variety are fragrant and have been bred in several colors; in one, 'Polypetalum', flower petals and leaves are so similar in size that the plant seems to have pink and green leaves.

R. poukhanense, the Korean azalea, is actually R. yedoense var. poukhanense. Although this plant is technically an evergreen azalea it is deciduous in cold climates. It is a low, spreading plant that is hardy to -15 F.

Girard Hot Shot - Large flowers in a deep orange-red to scarlet. Plants develop an orange-red leaf color in the fall for winter color. Grows to 2' tall and hardy to -15F.

Wow -- good info, thanks!

What do you know about the Robin Hill cultivars? It sounds as if they should all be hardy (is that right?)and there seem to be a number of "low" or "dwarf" varieties. (I actually just picked up two "Gillies" yesterday afternoon when I saw them in the local nursery. They are listed at 2 feet but I'm guessing now that I've read a bit that 3 might be more likely (so they may need to move to the back of this area, which is a shady bed along the front of the house, bordered by a stone path). These azaleas, whatever we get, will be in full shade from mid-April when the trees leaf out here in Connecticut through fall, if that makes any difference in our options.

Also, one of our local nurserymen has several Kuisianum ("Pink" and "Alba") listed as Zone 6. You're saying maybe that's overly optimistic?

I am going to check out the R. poukhanense ... they sound like an excellent bet!