Pushing the Parameters by Peter Kendall
As a site most advantageous for rhododendrons, the Cecil and Molly Smith Garden offers two species which greatly extend the blooming period of the genus. While coming into bloom outside the normal visitation days, these two rhododendrons are each stellar performers in their own realms.
Rhododendron moupinense
Photo by William Spohn
R. moupinense is a species native to western Sichuan, China and derives its name from the district of Moupin. First introduced into cultivation by E.H. (Chinese) Wilson in 1909, it begins flowering toward winter’s end and provides an enticement toward the coming spring. There are three forms found in cultivation; these range in structure from three to six feet tall. In configuration they run from lax to compact. The leaves are one to two inches long and half as wide; oval in shape, they are deep green and shiny on the upper surface while paler beneath; they are quite substantial and rigid for their size. The flowers are arranged terminally with from one to three flowers in the arrangement. The corolla is fringed and widely funnel shaped. The flower color is white to white-flushed pink with twin rays of spots on the upper lobe.
Planted in an area with good air drainage, the flowers of this temperate species are generally able to withstand a few degrees of frost. It should also be situation in a soil with excellent drainage as this species is often epiphytic (either on oaks or rock cliffs) in it’s native haunts.
Following the captivating bloom, R. moupinense pushes a bronzy red new growth which extends its allure for several weeks. What’s more, in its most common form, a bright exfoliating bark adds to its mature comeliness. This species is the parent of many notable hybrids among which are ‘Cilpinense,’ ‘Brick-a-Brac,’ and ‘Seta.’
Rhododendron auriculatum
Photo by Hank Helm
With summer’s culmination, a particularly inviting member of the genus rhododendron offers another attribute. Quite often, it first alerts us to its presence by it’s marvelous perfume. Harking back to the fragrance of R. fortunei in spring, this stately plant can reach twenty feet in height and is wider than tall. It’s mid-green leaves are up to one foot in length and auricled at the base—hence it’s name R. auriculatum. It’s flowers occur in a large loose truss, are frilled and generally white with a green touch at the base of the tube. It can flower as late as September in the northern latitudes. With it’s ensuing new growth, the young shoots are enclosed by enchanting red ribbon-like bracts.
It was introduced in to cultivation in 1900 by the same E.H.Wilson that later introduced R. moupinense. R. auriculatum can be a taxing plant to grow. It must have space, wind shelter and the proper amount of sun.
It is presently one of only two species relegated to Subsection Auriculata. It provides a number of worthy hybrids; perhaps best known is ‘Polar Bear,’ (R. diaprepes x R. auriculatum) bred in 1922 by J.B. Stevenson at Tower Court.
