American Rhododendron Society Plant Registry
Introduction: The following rhododendron and azalea names were approved and added to the International Rhododendron Register prior to November 1, 2007 by the Royal Horticultural Society, International Cultivar Registration Authority for the genus Rhododendron. The North American Registrar assisted the RHS by providing data for plants originating in North America.
References: Names conform to the rules and recommendations of the International Code of Nomenclature for Cultivated Plants – 7th Edition (2004). Color numbers refer to the RHS Colour Chart. Accompanying color names are taken from A Contribution toward Standardization of Color Names in Horticulture, R.D. Huse and K.L. Kelly, edited by D.H. Voss (ARS, 1984).
Format: Parentage lists the seed parent first, followed by an "(s)" if the direction of the cross is known; this is followed by an upper case "X" and then the name of the pollen parent. If either parent is itself a cross, the individual components within that cross are separated by a lower case "x". Parentheses are used only in describing the more complex crosses. Abbreviations are used where appropriate: (a) = azalea, (r) = rhododendron, (v) = vireya rhododendron, (z) = azaleodendron; H = hybridized by, G = grown to first flower by, R = raised by, S = selected by, N = named by, I = introduced commercially by, REG = registered by; dates are enclosed in parentheses immediately following the activity. Metric conversions of dimensions are reported in 5mm (0.2") increments for dimensions greater than 1" (25mm).
(r) 'Betty Spady': Elepidote rhododendron: R. yakushimanum 'Koichiro Wada' (s) X R. proteoides, Rock 147. H and G: Cecil Smith, Saint Paul, OR; N (2007) and REG (2007): Herbert Spady, Silverton, OR; I: Smith Garden, Saint Paul, OR. Fls 11/ball truss, openly funnel-shaped; 1.2" (30mm) long x 2" (50mm) wide, with 6 wavy-edged lobes. Color pale purplish pink (56A) in bud, opening inside nearly white tinged with pale purplish pink (56A), the dorsal lobes heavily spotted with deep purplish pink (55A); outside opening pale purplish pink (56D), each lobe striped with pale purplish pink (56A). Truss 3" (75mm) high x 3" (75mm) wide. Lvs held 3 years, 1.5"-2" x 0.5"-0.8" (40-50 x 15-20mm), oblong, broadly acute apex, cuneate to rounded base, down-curved margins; dull and moderate yellow green (147A-C) above with hairy indumentum on lvs. Color of indumentum moderate orange yellow (168D) when young and moderate reddish brown (174B) when mature; floccose on upper surface at first and then glabrous with age; felted and persistent below. Shrub 3' (0.9m) high x 3' (0.9m) wide in 20 years; dense habit. Plant hardy to at least 10°F (-12°C). Early flowering period. (Smith Garden No. 139)
Photo by Herbert Spady
(a) 'Corley's Cardinal': Deciduous azalea: R. calendulaceum, yellow-flowered (s) X R. calendulaceum, orange-flowered. H(1987), N (2000), and REG (2007): R. Oneal Smitherman, Auburn, AL; G (1992): Tom E. Corley, Auburn, AL. Fls single, 7-8/bud, 1-3 buds/dome truss, tubular funnel-shaped, with exserted stamens and pistil; 1.8" (45mm) long x 2" (50mm) wide, with 5 wavy-edged lobes. Color vivid reddish orange (34B) in bud, opening vivid reddish orange (34B) throughout, with a vivid yellowish pink (30C) dorsal blotch. Terminal inflorescence 3.5" high x 5" wide (90 x 125mm) from single bud to 5" high x 5" wide (125 x 125mm) from 2-3 buds. Lvs 2"-2.8" x 1.2"-1.5" (50-70 x 30-40mm), obovate, broadly acute apex, cuneate base; dull and moderate olive green (137B) above; hairless. Shrub 8' (2.4m) high x 8' (2.4m) wide in 22 years; intermediate habit. Plant and buds hardy to at least 5°F (-15°C). Mid April.
Photo by T. Corley
(v) 'Golden Retriever Mandy': Vireya (lepidote) rhododendron: ('Gardenia Odyssey' x R. laetum), selfed. H (2001): Graham Snell, Queensland. Australia; G (2006) and I (c2009): Pacific Island Nursery, Kea'au, HI; N (2007), and REG (2007): Richard Kruppa, Volcano, HI. Fls 6-7/flat truss, tubular funnel-shaped, 2.3" (57mm) long x 2.5" (65mm) wide, with 5 wavy-edged lobes. Color brilliant yellow green (149B) in bud, opening inside vivid yellow (14A) aging in 9 days to strong orange yellow (17A); outside vivid yellow (14A) aging in 10 days to vivid orange yellow (21A); unmarked. Truss 3.5" (90mm) high x 6.6" (165mm) wide. Lvs elliptic to obovate, acuminate apex, cuneate base, up-curved margins; semi-glossy and moderate olive green (137A) above, moderate yellow green (138B) below. Shrub 2.7' (0.8m) high x 2' (0.6m) wide in 6 years; intermediate habit; fls long-lasting (8-10 days on plant and 12-15 days as cut fls). Plant hardy to at least 38°F (3°C); buds, 48°F (9°C). Mid August and perhaps February-March. (Also known as “Mr Snell's 'Meadow Yellow' F2")
'Golden Retriever Mandy'
Photo by Cam Muir
(r) 'Margaret S. Coe': Elepidote rhododendron: 'Parker's Pink' (s) X 'Martha Phipps'. H (1990), G (1997), and REG (2007): Richard Murcott, East Norwich, NY; N: Vinny Simeone, Planting Fields Arboretum, Oyster Bay, NY. Fls 9/ball truss, broadly funnel-shaped, c 2.8" (70mm) long x 4" (100mm) wide, with 6 wavy-edged lobes. Color inside edge strong purplish pink (55B) shading to pale purplish pink (55D) with light yellow (11B) speckled markings in center; pale purplish pink (55D) outside. Calyx lobes c 0.1" (3mm) long. Truss 8" (200mm) high x 8" (200mm) wide. Lvs 5.5" x 2.5" (140 x 65mm), elliptic, obtuse apex, rounded base, flat margins; dull and moderate yellow green (137C) above; hairless. Shrub 5' (1.5m) high x 8' (2.4m) wide in 16 years; dense habit. Plant and bud hardy to at least -5°F (-21°C). Mid May.
Additions and Corrections:
'Tia': (published in Journal ARS, Vol. 61, No 3 Summer 2007); provenance should read H (1985): Willard W. Thompson, Sr., and G (1990): Thompson's Nursery; both Waldport, OR.