Snow is a Kurume Azalea. Snow's flowers are openly funnel-shaped, 1¾" across, single, hose-in-hose, white with a faint greenish-yellow blotch. [1-1/2" across]

Kurume azaleas are evergreen azaleas. They were imported from Kurume, Japan, to the Arnold Arboretum in Boston in the early 1900s and soon made their way into the nursery trade. They are hardy to Zone 7, +5° F. After five to eight years in the garden, most Kurume azaleas become dense 18- to 30-inch bushes with small glossy leaves. In spring the foliage is hidden by 1-inch flowers. Typical varieties are 'Coral Bells', medium pink; 'Eureka', similar to 'Coral Bells' but hardier; 'Glory', salmon pink; 'Hershey's Red', rose red; 'Hino Crimson', crimson; 'Hinode Giri', bright red; 'Lorna', bright pink; 'Polar Bear', white and 'Snow', white.

Japonicum are deciduous azaleas. Mollis Hybrid azaleas, derived mainly from R. japonicum (syn. R. mollis var. japonicum), bear large clusters of 2- to 3-inch flowers in late spring. The colors include many shades of yellow, orange and pink as well as white. Plants usually grow about 5 feet tall and are hardy in Zone 5 to -10° F.

Here is a link that might be useful: Evergreen Azaleas

Thank you Rhodyman. I'm thinking it must have been a Kurume. I had it for 25 years. It was always so full of blooms that you could hardly see the plant. Then I made the fatal mistake of trying to move it. It always amazed me because the only sun it got was early morning for maybe 2 hours. Thanks again. I'll see if I can find it in our area of Houston.

Cornelius Nursery is either owned or affiliated with Calloway's Nursey, which carries a lot of Kurume Azaleas over here. Call them and ask if they have the one you want.