Species In Our Midst
Rhododendron oreodoxa
and
Rhododendron oreodoxa var. fargesii

Rhododendron oreodoxa var. fargesii
Picture by Dick Brooks

Rhododendron oreodoxa and Rhododendron oreodoxa variety  fargesii.

These elepidote (without scales) rhododendrons are members of section Fortunei, subsection Oreodoxa. Oreodoxa means 'glory of the mountains' and was first described by Franchet in 1886.The epithet fargesii was named as a species in honor of its western discoverer, Pere Farges, 1844 -1912, French Foreign Missions in NW. Szechwan. D.F.Chamberlain in his revision of the taxonomy of the genus rhododendron has declared R. fargesii to be a variety of R. oreodoxa. They grow wild in the mountains (7,000-13,000 feet) in Chinese provinces of Hupeh, Szechwan, Kansu and Yunnan and are found both as understory plants in mixed woodland on bare slopes above tree line.

Both R. oreodoxa and R. oreodoxa var. fargesii, are 5 to 17 feet tall when mature. They are upright, well-branched and nicely shaped. Their bark is a roughish grey-brown. The leaves are comparatively small, up to 4 inches long and up to 1 3/4 inches wide and oblong to elliptic in shape.Leaves are leathery in texture; dark green above and paler, often with a bluish, waxy cast below. The leaf petiole is usually purple but sometimes pale green. Flowers are tubular-campanulate, (in the shape of a long bell), and range from white or pink to rose or purple-rose in color, sometimes with purplish spots. There are from 6 to 8 blooms per truss.

R. oreodoxa var. fargesii differs from R. oreodoxa in having a densely glandular ovary; R. oreodoxa having a smooth ovary. R. oreodoxa var. fargesii usually has rounder or more ovate (egg-shaped) leaves and  wider flowers. Cox, in his The Larger Rhododendron Species , says the distinctions between these two plants are more horticultural in nature (ie. a matter of appearance) and as such do not constitute grounds for being different species.

R. oreodoxa and R. oreodoxa var. fargesii are early, heavy bloomers and are vulnerable to late frosts. They benefit from being planted in a location that will shelter them from late frosts. Some growers complain about their habit of curling their leaves tightly in cold weather (more quickly than any other species, according to Cox!). Greer lists R. oreodoxa as hardy to -5°F(-20°C). R. oreodoxa var. fargesii is listed as plant hardy to -10°F(-23°C), but I know of an unprotected plant in Concord, MA (USDA zone 5) that never fails to bloom! They are both said to be easy plants to grow but we need more data for New England.

In England, forms of both have received Awards of Merit. Lansing Bulgin's book on plant hybrids and their parents lists only three crosses with  R. oreodoxa: 'Westfalenpark' from a cross with 'Doncaster', 'Pink Crest ' from a cross with R. thompsonii, and 'Rombergpark' from an unknown cross. He lists two crosses with R. fargesii: 'Farther' from a cross with R. morii and 'Earlybird' from a cross with R.williamsianum.

This is a lovely, vigorous species that deserves to be tried more in New England. It should be used as a parent in hybridizing, especially for its early-blooming characteristic.