Evergreen Azalea Ratings For The Philadelphia Region
By Franklin H. West, M. D.
Our honored dean of rhododendron and azalea hybridizers, Joseph B. Gable, wrote in the 1948 Rhododendron Yearbook: "The azalea series are probably being grown in the Eastern United States at the moment in greater quantity and variety than anywhere else in the world. And, though they are by no means always successful, or always hardy, there are so many sorts of great beauty that customers replace them regardless. With so much interest and such a general trying out of varieties in so many situations, the old rule of survival of the fittest will inevitably result in a gradual trend toward the planting of those that are more nearly permanent. There are far too many new azalea varieties in the trade at present and the situation is generally confused, but the future of the azalea as a common garden ornamental along the Atlantic seaboard is most definitely assured."
The Philadelphia Chapter membership certainly enjoys this interest in azaleas, and the most outspoken of the azalea buffs were appointed by past president Raymond P. Jefferis to an Azalea Study Committee.* We decided to apply the same rating techniques to azaleas as is currently done with rhododendrons. A preliminary rating was given to more than thirty evergreen azalea varieties best known to the committee, and a list of clones grown by committee members was assembled. This formed the basis of a four-page rating checklist, which was mailed to nearly all A.R.S. members within an eighty-mile radius of Philadelphia, accompanied by a letter requesting individual comment about each variety, including the number of years it was grown, hardiness, and its special qualities. In addition, we requested information about best varieties from the standpoint of foliage, color category, season of bloom, fragrance and best landscape appearance, and a choice for all-time favorite.
*Ross B. Davis, Jr., Philip A. Livingston, John B. McClatchy, Lloyd E. Partain, J. Russell Sonneborn, Mrs. Elsie Wilson, and the writer as Chairman.
The response to the rating checklist was very gratifying, particularly in view of the quantity of data we requested. Thirty-six replies were received, several of which were so detailed in their notations that they must have taken a day's work to prepare. We were greatly impressed with the accuracy and detail of the members' record-keeping, and particularly grateful to the contributors with the greatest experience. Many varieties reported were under an individual grower's observation for thirty years or more!
After the checklists were received and the information transferred to individual file cards by clonal name, the committee met to determine how the data should be tabulated. It was decided to establish the individual ratings by calculating the mathematical average of all reports received without weighting the figures in favor of those with the longest growing experience so that all factors influencing hardiness and desirability would have equal influence. No variety with fewer than five reports was given a regional rating number.
We see this as a continuing project and one far larger than the Philadelphia region alone. We hope each Eastern Chapter will initiate similar azalea rating studies in their own areas. With everyone joining in, the overwhelmingly overlong list of evergreen azaleas can be reduced to reasonable proportions, and Mr. Gable's and our complaint that there are too many azalea varieties could become a thing of the past.
PHILADELPHIA REGIONAL RATINGS INDICATED BY THIS SURVEY I. Species and Variants 1. R. mucronatum (Ledifolia Alba) 3/2, 17 reports. Not bud hardy in severe winters. 2. R. mucronatum 'Delaware Valley White' 3/3, 14 reports. Hardier selection. 3. R. mucronatum 'Sekidera' (Magnifica) 3/3, 9 reports. Rose blotch; faint scent. 4. R. obtusum 'Amoenum' 2/3, 14 reports. Terrible color, wonderful shrub. 5. R. pulchrum var. maxwellii 3/2, 9 reports. Spectacular color, plant barely hardy. 6. R. pulchrum 'George Lindley Tabor' 3/2, 6 reports. Large flower, hardy after 5 yrs. old. 7. R. indicum var. balsam 3/3, 11 reports. Dwarf, spreading, double flower. 8. R. indicum 'Hakatashiro' 2/3, 5 reports. Nice flower but not hardy enough. 9. R. indicum 'J. T. Lovett' 2/2, 9 reports. Nice flower, poor hardiness. 10. R. indicum 'Beni Kirishima' 3/3, 18 reports. Excellent late double. "A beaut." foliage, buds tender. 11. R. simsii var. eriocarpum 'Gumpo White' 3/3, 18 reports. Low growing, excellent 12. R. simsii var. eriocarpum 'Gumpo Pink' 2/3. 7 reports. Not as floriferous as white form. 13. R. poukhanense (single) 3/3, 15 reports. Early, lovely, very hardy, fragrant. 14. R. poukhanense (double) 2/3, 16 reports. Rapid grower, temperamental bloomer. II. Kurume Hybrids 1. 'Addy Wery' 3/2, 13 reports. Very fine red, not extra hardy. 2. 'Coral Bells' 3/3, 20 reports. Attractive flowers and foliage. 3. 'Guy Yerkes' 3/3, 10 reports. Nice pink. Needs some shade. 4. 'Hershey's Red' 3/2, 18 reports. Good hose-in-hose red; needs protection. 5. 'Hexe' 2/2, 8 reports. Tender buds, not hardy enough. 6. 'Hinodegiri' 3/3, 24 reports. Loud common red, hardy but not "ironclad." 7. 'Hino-Crimson' 3/4, 18 reports. Much better color than 'Hinodegiri', plus superb foliage. 8. 'Hinomayo' 2/3, 8 reports. Beautiful color, borderline hardy. 9. 'Pink Pearl' 3/2, 14 reports. Soft clear pink, fair foliage and hardiness. 10. 'Red Progress' 4/4, 8 reports. Very good, nice habit, very hardy. 11. 'Salmon Beauty' 2/2, 10 reports. Fades in sun, not very hardy. 12. 'Sherwood Orchid' 3/3, 10 reports. Hardy, has nice plant habit. 13 'Sherwood Red' 3/3, 11 reports. Glowing color, very satisfactory. 14. 'Snow' 2/3, 21 reports. Best in Del. and Md.; borderline hardy elsewhere; sunburns. 15. 'Yaye-Girt' 2/2, 5 reports. Not hardy enough. III. Kaempferi Hybrids 1. 'Beethoven' 3/3, 5 reports. Very good except north of Blue Mountain. 2. 'Carmen' 3/3, 8 reports. Very hardy, lovely soft color. 3. 'Cleopatra' 3/3, 5 reports. Very hardy and very good soft pink. 4. 'Fedora' 3/3, 11 reports. Very good. 5. 'Johann Strauss' 2/2, 7 reports. Large flowers, not so bud hardy, leggy. 6. 'Othello' 3/3, 14 reports. Does very well. Color may clash. 7. 'Palestrina' (With. Vuyk) 3/3, 21 reports. Upright white, very hardy and vigorous. IV. Pericat Hybrids 1. 'Mme. Pericat' 3/2, 8 reports. Attractive but very tender. 2. 'Sweetheart Supreme' 2/1, 8 reports. Too tender for outdoor use. V. Indicum-Satsuki Hybrids 1. 'Gunbi' 2/3, 5 reports. Good, but bud tender. 2. 'Gyokushin' 3/3, 5 reports. borderline hardy, lovely flower. 3. 'Kingetsu' 2/2, 5 reports. Tender, but perhaps best performer of group. 4. 'Mai-Hime' 3/3, 5 reports. Fades, marked tendency to sport. Tender. VI. Gable Hybrids 1. 'Big Joe' 3/3, 5 reports. Big bold flower, semi-evergreen. 2. 'Cameo' (not named by Gable) 3/2, 8 reports. Late double light pink. 3. 'Campfire' 3/3, 10 reports. Bright, "best red" for several growers. 4. 'Carol' 3/3, 7 reports. Nice effect even as flowers fade. 5. 'Caroline' Gable 3/3, 12 reports. Very good, late bloomer. 6. 'Chinook' (not named by Gable) 2/2, 6 reports. Nearly same as 'Mary Dalton'. 7. 'Corsage' (not named by Gable) 3/2, 5 reports. Nice flower, but fleeting. 8. 'Elizabeth Gable' 3/2, 14 reports. Best bloom in half shade. 9. 'Herbert' 3/3, 13 reports. Great bloomer, "hardiest plant I have." 10. 'James Gable' 3/3, 16 reports. A favorite, early red, hardy. 11. 'Jessie Coover' 3/2, 7 reports. Excellent flower color, less hardy than rest. 12. 'Jimmy Coover' 3/3, 6 reports. Low growing late red. 13. 'Kathleen' 3/3, 5 reports. Very hardy, full beauty with age. 14. 'Lorna' 3/3, 10 reports. Nice flower, tidy bush. 15. 'Louise Gable' 4/4, 14 reports. "One of the best." 16. 'Mary Ann' 3/3, 10 reports. Pretty and dependable; hardy. 17. 'Mary Dalton' 2/3, 9 reports. Early orange-red, hose-in-hose. 18. 'Mary Frances Hawkins' 3/3, 8 reports. Tall, "one of his best." 19. 'Mildred Mae' 3/4, 9 reports. A more compact 'Viola'; lavender. 20. 'Purple Splendor' 3/3, 18 reports. Hardy, thrives, some dislike color (same as #9 and #23). 21. 'Rosebud' 4/3, 22 reports. Low, dense, late pink double, light shade. 22. 'Rose Greely' 4/3, 24 reports. Fine bloom and shrub habit. "Best compact white." 23. 'Royalty' (not named by Gable) 3/3, 5 reports. Color similar to 'Herbert' and 'Purple Splendor'. 24. 'Springtime' 4/3, 10 reports. Tall early, bright clear pink. Hardy. 25. 'Stewartstonian' 3/3, 19 reports. Brilliant red, very good; pretty winter foliage. 26. H12G. Mr. Gable considers this the same as 'Bent Kirishima'. VII. Glenn Dale Hybrids 1. 'Ambrosia' 4/2, 6 reports. Apricot flower, barely evergreen. 2. 'Angela Place' 3/3, 5 reports. Low, very late large white. 3. 'Aphrodite' 3/3, 5 reports. Nice foliage, pretty pink, hardy. 4. 'Buccaneer' 3/2, 9 reports. Excellent if kept in shade-sunburns. 5. 'Cavalier' 3/3, 6 reports. Clean bright color; brilliant fall foliage. 6. 'Copperman' 3/3, 10 reports. Late, big flower; good plant habit. 7. 'Crinoline' 3/2, 5 reports. Late big ruffled pink; barely evergreen. 8. 'Cygnet' 3/3, 5 reports. Floriferous white, good branching habit. 9. 'Dayspring' 3/3, 7 reports. Earliest Glenn Dale, lavender pink, hardy. 10. 'Delos' 3/2, 5 reports. Prettiest double Glenn Dale, barely evergreen. 11. 'Dragon' 4/3, 5 reports. "Best red Glenn Dale." Brilliant. 12. 'Everest' 3/2, 5 reports. Fine white, late; buds not hardy enough. 13. 'Fashion' 3/3, 5 reports. Good hose-in-hose orange-red. Good foliage. 14. 'Festive' 3/3, 6 reports. "Flower tops, buds a little tender." 15. 'Gaiety' 4/3, 8 reports. Nice both for flower and foliage. 16. 'Geisha' 4/3, 12 reports. The best striped variety. "Tops." 17. 'Glacier' 3/3, 13 reports. Best foliage of all Glenn Dales. Buds somewhat tender. 18. 'Glamour' 3/4, 6 reports. 'Would not b° without this." 19. 'Greeting' 3/4, 8 reports. Fine glossy evergreen foliage. Hardy. 20. 'Joya' 3/2, 6 reports. Not too hardy. Large pink flowers midseason. 21. 'Kobold' 3/3, 5 reports. Deep velvety wine red, best in shade. 22. 'Martha Hitchcock' 4/3, 10 reports. Distinctive, flamboyant bloom. 23. 'Mayflower' 3/3, 5 reports. Superb color, hardy, fine shrub. 24. 'Moonbeam' 3/3, 5 reports. Enormous white blooms. 25. 'Niagara' 3/3, 5 reports. Reliable good white. 26. 'Prudence' 3/4, 5 reports. Splendid evergreen foliage and habit. 27. 'Sagittarius' 2/3, 8 reports. Foliage and plant like boxwood; buds quite tender. 28. 'Treasure' 3/3, 17 reports. "Much heralded but not as fine as R. mucronatum" VIII. Summary of Growers' Personal Preferences: (Including unrated varieties) Best early whites: 'Ivory', 'Rose Greely', 'H. H. Hume'. Best midseason whites: R. mucronatum 'Delaware Valley White', 'Glacier', 'Treasure'. Best late whites: 'Swanson', 'Moonbeam', 'Wavelet', 'Gumpo'. Best early pinks: 'Coral Bells', 'Dream', 'Eleanor Allen', 'Ohio', 'Merritt #23'. Best midseason pinks: 'Arcadia', 'Louise Gable', 'Gaiety', 'Billie'. Best late pinks: 'Rosebud', 'Crinoline'. Best early reds: 'Addy Wery', 'James Gable'. Best midseason reds: Gable's 'Campfire', 'Emblem', 'Dragon', 'Glamour'. Best late reds: 'Bent Kirishima'. Best early lavender: R. poukhanense Best midseason lavender: 'Purple Splendor', 'Herbert'. Best late lavender: 'Muscadine', 'Zulu'. Best variegated: 'Geisha', 'Mai-Hime', 'Martha Hitchcock'. Best landscape value: 'Bent Kirishima', 'Gumpo', 'Swansong', 'Glacier', 'Greeting', 'Delaware Valley White'. Best for fragrance: R. poukhanense. All-time favorite variety: 'Louise Gable', R. poukhanense, 'Ohio', 'Rosebud', 'Swansong', 'Delaware Valley White'.
Comments From Survey Contributors:
From James Wells, Red Bank, N.J.: "We are in a much colder area here and I think that my nursery must be especially cold because many plants which other people grow well, I cannot grow at all. 'Delaware Valley White' is a typical example. We have tried most of the Glenn Dales and find them almost without exception useless. By and large the best plants here are the hardier Gables: 'Lorna', 'Louise Gable', 'Mary Ann', and 'Mary Frances Hawkins'. The second group which is excellent here are the Kaempferi hybrids. Most of the Kurume hybrids are not hardy here with the exception of 'Hino Crimson'."
(Author's note: An analysis of the factors producing this state of affairs should make an interesting research project that might further illuminate the problem of regional hardiness, since Glenn Dales make a good show north of this location.)
From Roland deWilde, Bridgeton, N.J.: "Azaleas are plants I have grown for some forty years, and in that time I have come to the conclusion that I don't know very much about their hardiness. Last year all our plants were left out, and took what they had to all winter. Best blooms were 'Red' and 'Pink Progress', 'Hinomayo', the Kaempferi hybrids such as 'Othello', and the Gables, such as 'La Premier' and 'Herbert', Springtime', 'Louise Gable' and 'Caroline Gable' bloomed fair. 'Delaware Valley White' bloomed fair and kept all its wood. 'May Glory', which usually gets damaged, bloomed fine-I don't understand it yet. It's not always fair to generalize, but the hardiest azaleas usually are the least evergreen-witness most of the Kaempferi hybrids and a number of the Gable varieties. True Kurumes are hardest to keep-we continue to grow 'Snow', but it is apt to give trouble some years. I think the ideal variety is not yet available."
From H. A. Quinter, Auburn, Pa.: "We are located north of the Blue Mountain and this area is more severe in wintering results. 'Hino Crimson' is the best of Kurumes, but some plants suffer, according to exposure. 'Elizabeth Gable' is a hardy and dependable bloomer. 'Herbert' is hardy. 'Rosebud' suffers considerably, branches freeze. Kaempferi hybrids are hardy and dependable. All others are not at all dependable. In fact, many nearby azalea owners are discouraged with evergreen varieties and are not replacing those lost."
From Gordon Tyrrell, Winterthur, Del.: "The earliest azalea with us is Gable's 'Springtime' and R. poukhanense. We have rated many of the species highly. There is little point in introducing hybrids which are not improvements of species, which many of them aren't. A case in point is R. mucronatum, which is, with us, still the most dependable midseason white. 'Treasure' is less hardy and, though larger, not as pure a white. 'Ivory' and 'Wavelet' are highly thought of because they are respectively earlier and later than R. mucronatum. 'Glacier' flowers at about the same time as R. mucronatum, but has such exquisite foliage that it is worth a high rating. There are too many Glenn Dale azaleas -too many resemble others of the same group, especially true of many of the reddish pink tones. The Gable hybrids are distinct, dependable, high quality plants. Perhaps the finest is 'Louise Gable', which is one of the best of all azaleas. Also very fine are 'James Gable', 'Rose Greely', and 'White Star'. The Pericats are all very beautiful but not dependable with us. Even during the mildest winters there is considerable die back. We have discontinued growing all but 'Pericat Orchid', which is hardy.
"The Satsukis are in a class by them selves. With us they are quite likely to freeze out when young plants, and even the older plants lose buds in bad winters. Still, they are so distinct in color, size, and time of bloom that they are worth a fuss. Some which have proven themselves with us are 'Howraku', 'Seigetsu', 'Kowkoku', 'Ta-ma-Sugata', 'Mai-Hime', 'Wakae-Bisu', 'Joh-Ga', 'Gunbi' and the Gumpo clones, which are outstanding."
From Mrs. Elsie Wilson, Narberth, Pa.: "With few exceptions, all azaleas are beautiful and have a place in somebody's garden. We certainly do not see colors alike. Over the years, we have given up many beautiful azaleas: either they were not dependable, or their color was hard to get along with, or we found a better red that didn't fade so soon. As I see it, the great difficulty of such an undertaking as azalea ratings is that personal taste in color differs so widely. Also, in one garden, no trouble in hardiness; in others, 'need protection'. For instance, 'Snow' and 'Pink Pearl' make twenty-five per cent of the azaleas I use for pink and white. We never lose them and they have been where they are for twenty-five years or more. The soft pink of 'Pink Pearl' blends with reds, lavenders, and stronger pinks. I wouldn't know how to put a garden together without them. All Satsuki hybrids are hardy here, if the rabbits leave them alone. On the other hand, all the beautiful Pericats I have tried do not thrive here. My advice would always be, you never can tell how an azalea will grow, how it fits in, whether or not you will like it year after year, until you try it yourself."
Many other varieties are being grown in our region, but not yet by enough growers to assign rating numbers to them. The evaluation of these additional varieties will be a continuing task for our Azalea Study Committee. In the case of the rated varieties, we can expect some changes in the rating numbers as more reports are received. With these two limitations in mind, the reader can refer to the azalea ratings in this report, and with some confidence pick out the best varieties by two yardsticks: their popularity, measured by how many of our 36 reporters grow them, and their beauty of bloom and bush, as measured by the rating numbers.