A series of reports on rhododendron species and hybrids listing habit of growth, color, size and shape of flower, size of truss, parentage in the case of hybrids, and blooming dates starts with the following reports in this issue of the A.R.S. Bulletin. These reports come from the Portland and Willamette Valley area in Oregon. Others from various locations throughout the United States will follow in future issues of the Bulletin.
Notes on Early Yellow Species
The Portland region rhododendron fancier always enjoys the coming into flower of his earliest sorts for they are the real sign of spring. Perhaps the first coming to my attention this season during the first half of March were the R. lutescens for I have a group of them in a very sunny spot of light soil in which they thrive freely. Their foliage almost privet like is of bronzy hue borne on branches of rather upright nature and the plants at the present about 30" tall are a perfect sheet of sulphur yellow blossoms. The individual flowers resemble azaleas more than rhododendrons as they are about 2-2½ inches in diameter and come in clusters of 3 usually along the branches. Their blooming period extends over a period of 3 weeks to a month but occasionally is interfered with by hard frosts. Yet even with such a handicap the sight of a plant in full bloom is a thrill to every one who sees them and few are our spring seasons that do not give them a chance to display their charm for some time. A feature that makes the R. lutescens especially charming is the glossy bronze of its foliage often fully as elegant as the well known Japanese maples.
Another of our early yellow flowering species is R. flavidum which follows closely the blooming season of lutescens, but here we have a lapponicum with tiny evergreen leaves of rather dull green color with small twiggy branches bearing terminal small clusters of pale yellow blooms that show well in the rock gardens where the blue-green foliage of R. fastigiatum furnishes the proper setting for the yellow flowers. Skilled planters make use of the dwarf blue green junipers so well suited to rockery effects for combinations with such rhododendrons. R. flavidum in our climate here is inclined to grow straggly unless exposed to full sun at all times. For a neater habit of growth and more compact and better colored flowers R. chryseum is much preferable although more finicky in its soil and growing demands.
- J. G. Bacher
During recent years many new hybrid rhododendrons have been imported from abroad. Each Spring and Summer has brought the anticipation of fine new forms and colors. The following is a partial list of plants that bloomed this spring, some for the first time in this country. Succeeding A.R.S. Bulletins will have more information on new hybrids, and it is hoped that a complete list can be catalogued.
R. 'Albatross'. This hybrid of R. 'Loderi' x R. discolor has flowers that are pure white over 5 inches across, borne in an immense truss. Blooms May 23.
R. 'C. P. Raffil'. A hybrid between R. griersonianum and R. 'Britannia'. A medium sized loose truss of 10 to 11 flowers about 3 inches across. The color is a brilliant red, unspotted. In full bloom May 28.
R. 'Arthur J. Ivens'. An attractive low growing hybrid (R. williamsianum x R. 'Houlstonii'); has rose pink, almost flat flowers nearly 3 inches across. Bloomed April 15.
R. 'Naomi' (R. 'Aurora' x R. fortunei) An upright growing plant with shell pink flowers shaded orange in the throat four inches across, and 9 to 11 flowers in the truss. In bloom May 4.
R. 'Diane' (R. campylocarpum x R. 'Mrs. Lindsey Smith') Probably a Var. of R. 'Zuyder Zee'. 3½ inch pale yellow flowers in a large truss. The 10 to 12 blooms are unspotted. March 26.
R. 'China'. This hybrid was obtained by crossing R. wightii and R. fortunei. Pale yellow 3 inch flowers, fifteen in number in a lax truss. Bloomed April 22.
R. 'May Day'. An interesting plant, the result of crossing R. griersonianum and R. haematodes. The 8 to 10 crimson flowers borne rather loosely show to best advantage in the sun. Blooming May 4 this year.
R. 'Seagull'. This handsome plant carries its 4 inch, white flowers in a high truss. The parents are R. sutchuenense x R. 'Loderi'. Bloomed March 15.
R. 'Golden Horn'. (R. dichroanthum x R. elliottii) A loose truss of orange-red, trumpet shaped flowers, 8 to 10 in number. Bloomed about April 24.
R. 'Goblin'. Light pink to salmon bloom, carried in a loose truss. Each flower 3 inches wide with an unusually large calyx. The parents are R. 'Break of Day' x R. griersonianum. In bloom on May 10.
R. Euryalus'. A hybrid between R. 'Nereid' x R. griersonianum. Six to eight light scarlet flowers are two inches across, borne in a loose truss. The calyx is large and of a darker red. Bloomed fully on April 10.
R. 'Arthur Osburn'. A compact bush with unusual red flowers. When the bloom is caught in bright sunlight a very noticeable two tone effect is established between red and bright scarlet. The parents are R. didymum x R. eriogynum. Bloomed about June 10.
- Rudolph Henny