QBARS - v8n1 Past, Present and Future Development of The Trial Garden

Past, Present and Future Development of The Trial Garden
By Ruth M. Hansen

It was just three years ago on the 21st of October 1950 that the first plantings were made on the Test Garden Island. At that time it seemed a very distant day when we could visualize the entire Island planted from end to end. Since that first initial planting an almost herculean task has been accomplished by the indefatigable work on the part of a few faithful workers of the Portland Chapter.
Those who have followed the accounts of this development, as related periodically in the Bulletin, are amazed at the fulfillment of our dream within such a short time. Every member of the A. R. S. can be justly proud of this Test Garden for it is a part of every one of us, whether we have one rhododendron or a whole collection.
Today the Trial Garden and Park contains over 2,000 rhododendrons and it is planted from end to end. Of this number there are about 300 named hybrid varieties, about 125 varieties of species and about 100 named varieties of Azaleas. As this is a Rhododendron Park as well as a Trial Garden, one may see many of the old favorites as well as the newest introductions. All plants are clearly labeled so the public may compare these plants with their own as to manner of growth and correct naming. The Plant Markers given the Botanical Name, Common Name, Native Habitat, and Hardiness and Quality Rating if known. There are now 14 plants actually under Test Conditions.
Within the past year a Rockery has teen developed for the dwarf varieties of rhododendrons. Again this work was all done by the "willing few" of the Society and again our Commercial and Amateur growers generously donated plants. In this Garden both species and hybrids are planted side by side with no thought of segregation. Due to our cool Summer the dwarfs have made remarkable growth and have already taken on that (settled look) proving that they are perfectly happy in their new home.
Another asset to the Test Garden is the acquisition of a collection of rhododendron species from the 7948 Dr. Rock Expedition. The Society not only endeavors to maintain a complete collection of these plants but to identify the specimens grown under each number. In many instances this can only he done as the plants bloom. Last Spring when Dr. Rock visited our Trial Garden he was greatly pleased in seeing how the seedlings had grown and how they were labeled and cared for.

R. auriculatum R. sutchuenense
Fig. 4. R. auriculatum showing its last
bloom in the Trial Garden at Crystal Lake
Springs Island. This specimen over eight
feet tall has bloomed the last four years of
its sixteen year total.
Roth photo
Fig. 5. R. sutchuenense . This plant is
usually  one of the very first to bloom at
the Trial  Grounds at Crystal Springs
Lake Island.
Bacher photo

Bloom may be seen in the Trial garden from February through August. The earliest species to bloom are R. sutchuenense , mucronulatum and lutescens . Of course the main bloom comes during May and June. July and August bring forth the very late ones as R. auriculatum and R. ungernii . This gives one the chance of seeing rhododendrons in bloom for seven months of the year and it is my belief that no other plant Genus produces such a long blooming period. Other plant materials as Magnolias, Japanese Maples. Franklinia and Ericaceous plants complimentary to rhododendrons and azaleas have been introduced among the plantings.
Though our present Island is only of four acres we have almost unlimited ground at our disposal when it becomes necessary to expand. Already a foot bridge is contemplated to connect our Test Garden to an adjoining Island.
As one advances through the rhododendron realm from hybrids to species. small-leaved varieties to large-leaved varieties his subconscious mind is gradually awakened to an entirely new type of rhododendron: these are the aristocrats of the Rhododendron Genus, commonly known as the more tender flowering varieties from the sub-tropical belt of the Himalayas and Western China. Most of these are epiphytes. that is they grow high up o» branches of trees in their native habitat: though they require nothing from their host other than a home as they manufacture all their own plant food. Among these are the most fragrant, alluring and charming of all plants. Without doubt their fragrance rivals that of the Lilies.

R. lindleyi
Fig. 1. R. lindleyi
Brydon photo

Recently the Trial Garden was made the recipient of an outstanding collection of these tender varieties, both species and hybrids, mainly from the maddenii , edgeworthii and boothii series, sub-series included. A more delicate and beautiful sight is hard to imagine than seeing a plant of lindleyi , (Fig. 1) 'Victorianum', bullatum , etc., in bloom. Aside from their tubular lily-like corollas they are deliciously fragrant and positively breathtaking in their beauty. Some as R. exonensis have a very spicy fragrance. These treasures from the sub-tropics are for the benefit of everyone, not just a few.
Also included among these tender varieties are some of the finest yellows. R. burmanicum , described in the October 7953 Bulletin by Roy T. Hudson is undoubtedly one of the best. I saw a mass planting of R. burmanicum in bloom two years ago in Golden Gate Park and it was truly the most outstanding rhododendron there. Its golden flowers will never be forgotten. Possibly the Boothii series contains the largest number of yellow species, all of which though having small flowers, offer wonderful opportunities to the hybridist.
Amass planting of the more hardy varieties of the tender rhododendrons such as R. 'Fragrantissimum', R. 'Countess of Haddington', R. johnstoneanum and R. exonensis were planted on the Island last year. Even though these plants will survive our coldest winters their buds are frequently damaged by early frosts. With the erection of a Coolhouse these same plants would bloom more profusely and he twice as attractive.

R. arboreum roseum R. arboreum
Fig. 2 R. arboreum roseum
Brydon Photo
Fig. 3. R. arboreum . This splendid blood red
form  seems the least hardy of all the Arboreum
varieties and can only survive under glass in the
Pacific Northwest, thought it was grown outdoors at
the University of  California at Berkley.
Brydon photo

At a recent meeting of the Board of Directors unanimous approval was given for the construction of a Coolhouse in the Test Garden. The way is now open for donations to help in the financing of this project. We also have an especially large specimen of a very fine blood-red R. arboreum (Fig. 3) and R. kyawii on the waiting list to be admitted to the proposed Coolhouse. If anyone wishes to make any contribution to this worthy project we would sincerely appreciate it.

R. arboreum album
Fig. 7. R. arboreum album . A much hardier
form of the series that will stand more exposure
than either red forms.

With the addition of a Coolhouse in the Trial Garden a tremendous educational step will have been taken for we believe that it will house, for public use, the most complete collection of tender rhododendrons outside of the San Francisco area. It will also give visitors the opportunity of actually seeing one of the most variable collections of rhododendron species and hybrids to be seen anywhere. Every type of rhododendron will be represented: that is every type from little prostrate growers, to shrublets, to larger shrubs on up to the large-leaved tree types and last the epiphytes which will he found in the Coolhouse. This Trial Garden will he of great horticultural value and serve as a study area for present and future rhododendron fanciers. It has already become a Mecca for those who are interested in this remarkable plant Genus. And when one remembers that all the plants in this Garden, with the exception of a very few, have been donated by nurserymen and amateurs it shows the remarkable cooperation and good-will of our local members in helping to create a Garden that will serve the public as long as there is a City of Portland.