QBARS - v16n4 Rhododendron Notes

Rhododendron Notes

The long cold fog shrouded summer in central coast-wise California, the coldest in sixty-two years, has at last come to an end and now what will winter bring? The cold weather has been favorable to bud development and all looks well for a good season. The only good result of our miserable weather has been freedom from leaf burn. R. spinuliferum , yakushimanum , davidsonianum and odoriferum wish us officially to thank the weather man.

In my garden there has been more branch blight or die back than ever before experienced, probably the usual unusual California weather. It may be interesting to note the R. maddenii appear to be completely immune from this trouble.

The first plant to set flower buds is a maddenii hybrid 'Victorianum' in May, followed closely by 'Royal Flush Orange', the others follow along, some just now setting buds.

R. nuttallii has not set buds and probably will not do so this year, too busy growing, a pity because our plant eight feet tall is a beautiful sight in full bloom.

An interesting experience with R. veitchianum , it set buds in June and started a heavy second growth in July. We removed all the first set of flower buds and now the second growth has a bud on each terminal with three times the original amount of flower buds.

We had a different experience with that "low growing" R. 'Unique' now eight years old and five feet high. It set the largest flower buds it has ever carried but by mid-August the second growth started to appear: we pinched it all off as the plant is too large now. The second growth stopped by September 1st and the flower buds are still growing in size. It appears that pinching off the second growth will save the buds this year. Will report on this later.

- Edward H. Long, California Chapter


With all due respect to the lovely stands of rhododendron macrophyllum on the Olympic Peninsula of Washington, those along the Oregon Coast (U. S. Highway 101) are as lush as we have ever seen. Their predominant companions, interwoven with them into a fabulous tapestry, are arctostaphyles columbiana , vaccinium ovatum , myrica californica and gaultheria shallon . The canopy above, composed of pinus contorta in some instances and picea sitchensis in others, has been formed by ocean winds into shapes reminiscent of trees in Japan.

It is almost enough to make a gardener weep with frustration that these stunning effects cannot be obtained in his own garden without great expense, while here they are by the hundreds on all sides. Here one could merely clear a place for a house and cut some paths, as the landscaping is already in place. The truth of this statement may be observed in the camping grounds of Honeyman State Park.

The secret of the dewy-fresh, dark green, glowing health of the plants is no doubt mostly due to the continually moist air and "Oregon mist" they receive. Also, summers are usually cool, with September and October bringing the warm, sunny days.

A trip along the Oregon Coast is worthwhile for the flora alone. The discordant note is the absence of architectural styles to complement the magnificent natural setting.

- Ruth Jacobson, Seattle, Wash.


The Species Project is expanding somewhat, in number of species being studied, and in number of chapters involved. We would all like to know where we can see plants of species Rhododendron true to name, and to know where really superior forms may be found. In some areas this information, at least with respect to a number of species, may already be available. In other parts of the country the species are relatively unknown. This project should eventually result in the superior forms, and help to determine whether those forms we have considered to be superior are really the best.


In his April talk before the Portland Chapter on Mrs. Berry's garden the writer evidently left the impression that many of the plants which have not been identified are natural hybrids. In this garden of over 5000 rhododendrons, most of them raised from seed collected in the wild, there undoubtedly are new forms of species. There could even be new species. Authorities visiting the garden the day before the International Conference of 1961, said that a form of R. sphaeranthum is the deepest pink in cultivation. A most unusual plant with red buds opening to creamy yellow flowers with edges lined and blotched red, was said to be a form of R. wardii , not before known.

There are hundreds of other fine plants many over fifteen foot in height, most of them over 25 years old. Many forms of R. forrestii , a group of over 30 three foot R. glaucophyllum are a mass of flowers in the spring. An unusual form of R. brachyanthum has a big mahogany-red blotch on one petal. There are two fine plants of the rare R. pentaphyllum always covered with bright rose-pink flowers in late March and early April. From seed of R. smirnowii , growing alongside and apparently identical to the well known form, is one with white flowers. These plants are above seven foot in height. The fine forms of plants in this famous garden are being propagated, will be given variety names, and become available in a few years.


Plants such as R. wardii , R. puralbum and others of the Thomsonii series, it seems to us, demand more perfect drainage conditions than many of the other species. We often plant them with a half wheel-barrow of coarse gravel six inches below the plant ball. Also dig an extra large hole and fill it with a mixture of good garden soil, peat, sand and pea size gravel.


A hillside planting location does not always assure perfect drainage. Some years ago we dug thirty or more quite old dwarf rhododendrons out of a hillside in a private garden. They had been there for years but the past season root rot had developed. We found a very thin layer of good topsoil with heavy clay underneath. The plants had actually been set out in pockets in the clay which held water and prevented drainage, encouraging the development of root rot.

- Bob Bovee, Portland, Oregon