Commentary: The Problem in Species Collecting
South Surrey, British ColumbiaCanada
Most people know the "Five Stages of Rhodoholism," which charts the increasing obsession of rhododendron lovers. Stage Four is when admiration for rhododendron species begins to take over and thus, as the Baby Boomer population ages, we should expect an increasing demand for choice rhododendron species.
Surprisingly, it is not that easy to find named forms of species. The Rhododendron Species Foundation and a few specialty nurseries in the U.S. sell select forms, but most growers sell stuff that has probably been grown from seed and is likely to be quite variable depending on the species. Furthermore, some plants sold as species are actually hybrids, a situation that is quite disturbing.
The ARS does not seem to encourage the recognition of select forms, and most named forms originate from Awards of Merit given by the Royal Horticultural Society (RHS) in England. Even when you find a named form of a species it is not always easy to find out what characterizes that particular form. I purchased Rhododendron schlippenbachii last year ,a form called 'Sid's Pink'. I have yet to find out who Sid was and what is special about his pink. Many people buying a plant today, in response to seeing a beautiful mature species, may be very disappointed in about five years' time when they discover that their prized plant does not have the special characteristics they had assumed all along it would have.
This is a frustrating situation for those of us who are not interested in yet another gross yellow hybrid and would rather that the species we purchase are choice. It is not just an issue of flower colour and foliage quality. Different forms exhibit different behavior regarding disease resistance and time of flowering. In particular, hardiness is known to be quite variable in a single species depending on where it was originally collected. For example, there is a plant of R. sinogrande in the Valley Garden in Windsor Great Park that has survived severe frosts for over 20 years and is now about 20 feet high. It would appear that forms of sinogrande collected by Kingdon Ward, especially from his last collection, have early new growth and are therefore more hardy than those collected earlier.
The situation in the UK is not totally satisfactory either. Writing in the RHS Rhododendron and Camellia Year Book in 1956, Kingdon Ward was very concerned that less and less attention was being paid to collectors' field numbers, which is a matter of some consequence for the large and complicated genus Rhododendron. He noted that it is as important to distinguish a particular species as it is to distinguish a nurseryman's form of any other well-known plant, and the easiest, certainly the best way to distinguish it, is by the collector's number. He also observed that there are hardier and more tender forms of sinogrande, and when the best three or four forms have been selected by trial and error, the inferior forms should be scrapped except for a specimen or two in complete collections. Back in 1956, Kingdon Ward had an acerbic comment on the "monstrous army of hybrids." I wonder what he would have said today!
David Sellars is a member of the Fraser South Chapter.