JARS v52n4 - Rhododendron luteum 'Golden Comet'

Rhododendron luteum 'Golden Comet'
A New Era in the History of the Rhododendron Species Foundation
Steve Hootman
Federal Way, Washington

With the naming and registration of Rhododendron luteum 'Golden Comet', the Rhododendron Species Foundation (RSF) has taken the next logical step in its continuing evolution. As the first selected clone to be introduced by this organization, 'Golden Comet' represents only the beginning of our developing clonal introduction program. Through careful selection and thorough evaluation, the RSF has not only the opportunity but the responsibility for distinguishing clones of merit grown from documented, wild-collected seed. As a long-term commitment of space and time, this is usually not possible for the home gardener or collector. In this manner we are not only fulfilling our mission but providing a service to the rhododendron public by producing correctly named and registered superior species material. The old policy at the RSF of only asexually propagating selected "superior" clones collected from British gardens was fine when that was our only recourse. Times change, however, and I for one saw no reason to continue propagating and distributing the same material year after year, waiting for a garden in Great Britain to name something and hopefully send us a cutting. In 1993, the RSF initiated a seed propagation program to supplement the cutting and grafting programs which were inadequate in many respects. This new program produces a tremendous amount of new and often quite exciting material. This raw material allows us to evaluate large groups of related seedlings, specifically selecting for those individual clones superior in form, foliage or flower as well as for general garden-worthiness. The vast majority of this exciting material is derived from seed collected in the wild, often representing taxa new to cultivation.

A bonus to this program is that we are better able to fulfill our mission of species conservation through cultivation and distribution of a wide selection of material grown from documented wild-collected seed. We still asexually propagate and distribute the older, though still quite popular, clonal material but now also have the opportunity to select out exciting new material. Done correctly, this process is a lengthy one, especially in a genus like Rhododendron , members of which often take many years to mature and fulfill their potential. Only then can they be evaluated and selected out for asexual propagation and eventual distribution - obviously, a lengthy period of time to wait in situations such as the recently introduced big-leafed species R. kesangiae and sinofalconeri . Of course, this is another benefit of growing from documented seed and distributing the admittedly un-evaluated seedlings. It may not grow into an award winning form but at least you have one!

Fortunately, there are isolated incidents in the past history of the RSF in which groups of species seedlings were grown from wild-collected seed. Several different Eastern azaleas are represented in this fashion as well as a group of 24 plants of R. luteum grown from seed collected wild in Turkey. The seed was collected in the hills near the Black Sea by Dorothy Ann Robbins, daughter of species collector and former RSF President Fred Robbins. The seedlings were planted out in 1976, and in 1992 I began the evaluation process, noting one clone in particular as outstanding in flower and foliage as well as habit. Your average R. luteum is itself an outstanding azalea, with showy fragrant yellow flowers produced over a long season from mid to late spring and brilliant fall foliage color of red or purple. Combined with an ease of culture in a wide range of situations and adaptability to most typical rhododendron-growing climates (hardy to -20°F), this species is a stunning addition to the garden or landscape. The flowers of future 'Golden Comet' were larger and of a deeper yellow color with many more per inflorescence than typical so that this clone remains in bloom far longer than any R. luteum I had seen. It was also the last R. luteum to drop its leaves each autumn, often retaining its bright scarlet foliage well into November. The growth habit was outstanding, with good horizontal branching for a nice wide and balanced appearance. It has also proven to be quite resistant to the dreaded powdery mildew which typically afflicts the foliage of this species in the summer months, causing an unsightly appearance and even defoliation. After several years of evaluation and realizing that this was the "real thing" and not just some jazzed-up garden origin R. luteum with a little Exbury azalea blood in it, I decided to name and register 'Golden Comet.'

After garden manager Rick Peterson suggested the name, I handed the responsibility of producing and marketing our new gem to Richie Steffen, RSF propagator. Richie spoke with Briggs Nursery, long-time supporters of the RSF, who agreed to tissue culture approximately 2,000 liners of the clone for our use. We are pleased to finally offer this exciting new selection which will be available in the spring of 1999. This clone can only be purchased from the Rhododendron Species Foundation and will be available through the distribution catalogs as well as the garden gift shop. Large plants of 'Golden Comet' will be available at the 1999 ARS Annual Convention.

Steve Hootman is the curator of the Rhododendron Species Foundation in Federal Way, Washington.