JARS v47n4 - Notes From the Vireya Seed Exchange

Notes From the Vireya Seed Exchange
Bill Moyles
Oakland, California

This year the ARS Vireya Seed Exchange received over 40 requests for seed and distributed over 400 packets. Approximately 25 percent of these requests came from overseas ARS members. This was the first year in some time that we were able to offer at least a bit of wild collected seed - Alan Clark's collection from Vietnam and an anonymous collection ( R. buxifolium ) from Mt. Kinabalu (Sabah). Where are the Peter Cox/Warren Bergs in Vireya land? Papua New Guinea calls!
In lieu of wild collected seed, there were some fine hand pollinated species seed contributed by our New Zealand and Australian connection. Needless to say, without the contributions from the southern climes - including Leslie Riggall in South Africa - our list would be considerably shorter. We were able to offer R. blackii described by its contributor Graham Smith of the Pukeiti Rhododendron Trust in New Zealand as a magnificent red worth any effort. Graham Smith has been a faithful contributor of both species and hybrid seed over the past several years.
Several forms of the Australian endemic R. lochiae were listed courtesy of Jack O'Shannassy and the Australian Rhododendron Society. And Jack Wilson, ex-president of their society, continues to send seed. One of Australia's top hybridizers, Brian Clancy, sent along seed of the classic yellow R. laetum and we are hoping for some second generation seed from his latest hybrids. Along with John Rouse, a major contributor for many years, Graham Snell and Harold Lewis, Australia is always well represented.
Our species list also included several selections of the "white giant" R. leucogigas , R. konori , R. macgregoriae , R. kawakamii and others. Some seed is still available.
For me this year's hybrid seed seemed to offer the most exciting possibilities. Os Blumhardt of New Zealand surprised us and sent along a ton of seed of several R. saxifragoides crosses. Rhododendron saxifragoides is a high elevation alpine dwarf, mat-forming and growing in bogs that drop to near freezing every night - difficult for most of us to grow and perhaps even more difficult to obtain! Blumhardt's crosses show exceptional vigor. His second generation (F2) cross of [( R. laetum x R. zoelleri ) x R. saxifragoides ] x self is especially interesting showing significant variation and wiry 2 inch roots on inch seedlings. A limited amount of seed from these crosses is also still available.
California's current vireya leader, Bill Moynier (a Peter Sullivan disciple), always contributes seed of crosses involving the "bigs": R. leucogigas / konori / phaeopeplum / laetum / aurigeranum . Foliage, fragrance, elegance. No greenhouse should be without at least one population from Moynier seed. Complex hybrid seed based on his material and the older English hybrids is often available from our sole contributor from India, M. S. Viraraghavan.
Then there are the 1990 R. hellwigii / R. konori , et al., crosses from John Rouse - marvelous foliage on strong plants: big spatulate, dark green matte foliage, as yet un-bloomed but worth the price just for foliage. Fresh seed of a new batch of his R. hellwigii crosses is available.
Vireya seed, and especially hand-pollinated species seed, is always in short supply. We try to solicit seed from all sources. If you are a source or know of one, please let us know. Royal Botanic Garden Kew and Edinburgh contributed seed in 1990 and we hope they will be able to contribute again. Wild collected seed would be met with great cheers of approval!
Although vireya seed is listed annually as part of the general ARS Seed Exchange list, seed can be obtained most any time of the year. I do my best to respond to inquiries as to what is available. All vireyas do not bloom in the same "season" and as a consequence new seed can come in at any time. To retain viability, it is stored in the freezer at 0°F and is generally carried over from year to year until it is all distributed. If you are unfamiliar with vireyas I can always put together a "mixed bag" of three or four packets for you to try. If you have not received the ARS Seed Exchange list in the past you must request one from Linda Wylie.
The annual list includes only the current year's and 1-year old seed. Older seed is always available, but viability is often unpredictable. I have germinated 4-year old seed and have had no luck with some 2-year old seed. But it is always worth a try.
Growing on vireya seed requires a bit more attention to detail than does everyday rhododendron seed. I am a satisfied user of milled sphagnum and fine perlite as a germinating medium under fluorescent lights. I prick out new seedlings into a plastic tray containing milled sphagnum, courser perlite and ⅛ to 1/16-inch bark (2 parts moss, 1 part perlite, 1 part bark). I close this container down under framed plastic wrap (as per a "covered wagon") and put it back under lights: warmth + high humidity + light fertilizer = (with luck) 2 to 3-inch seedlings in six months or so. A detailed "guidelines" paper describing the process is available for those interested.
I have been handling the distribution of vireya seed since 1987 and would be most interested in hearing from anyone who has bloomed Vireya Seed Exchange seed. I am always interested in germination results - good and bad. If you have problems, let us know. Perhaps we can help. Vireya seed collected when ripe and stored at 0°F should retain viability over a minimum of two to three years.