Species In Our
Rhododendron aureum is an elepidote species of the Ponticum subsection. It is a small compact or prostrate shrub first described by Georgi in 1775. It has a wide distribution from the Altai mountains in West Siberia to the mountains of Northern China, Kamtschatka, Sakhalin, and Kurile Islands, Korea and northern Japan at elevations of 5000-9000 feet. Photographs of R. aureum blooming in the wild show it on exposed grassy alpine slopes or scree conditions.
R. aureum is very hardy rated at -15°F by Greer. The variety R. aureum var. aureum is cultivated and is described here. There is a another variety R. aureum var. hypopitys with larger leaves forming a 3 feet tall shrub under spruce and fir woods in Siberia but it is not in cultivation.
The specific name aureum mean golden and refers to the cream to yellow flowers. In older references you may see the obsolete name chrysanthum used. The flowers are 5-lobed widely funnel shaped 1-1 ½ inches long. The 3-8 flowered inflorescence is in proportion to the overall dwarf size of the plant and leaves. The leathery glabrous leaves 1-4 inches long are variable in size even on the same plant. Leaves are held at least 3 years as are the leaf scales or perulae. The internodes are very short. A mature plant can reach as high as 2 feet in 10 years or be as prostrate as 4 inches.
From Honshu, Japan there are 2 natural hybrids of R. aureum. X nikomontanum is a hybrid between aureum and brachycarpum that is more vigorous than aureum and intermediate in habit with pale yellow flowers. The other natural hybrid x kurohimense is aureum x degronianum a result of these two species coexisting at lower elevations in Honshu.
R. aureum and the natural hybrid x nikomontanum have been used extensively in breeding to get hardiness, yellow and dwarfness. W. O. Delp used aureum and 'Seredipity' ( degronianum ssp. yakushimanum x aureum) in breeding programs often as the pollen parent. Ben and Marion Shapiro used x nikomontanum in their breeding program. Our chapter's Dick Brook crossed 'Apricot Glow' with aureum to select 'Little Sara'.
R. aureum is slow to flower and some forms are shy flowering. I have 4 plants of aureum all of which are prostrate and have never flowered. They were obtained through Plants for Members donated by Polly Hill. They do not require much space along the path in the sunnier spots in my garden. It also has the dubious reputation of being a good indicator plant for black vine weevil damage.
Sally Perkins, Salem, NH