May 24, 1919 



HORTICULTURE 



491 



AZALEAS OF INTEREST TO NURSERYMEN 



An azalea now blooming at the Arnold Arboretum is 

 one of the most promising new plants which has been 

 introduced for a longtime. II comes from Korea and is 

 known as Rhododendron Schlippenbachii. Because of 

 us remarkable hardiness it can be planted anywhere in 

 the United States with full confidence. Moreover, there 

 is every reason to believe that it can be readily cro sed 

 with the tender greenhouse azaleas, so as to produce a 

 new race of these plants for American gardens. Prof. 

 Sargent thinks so well of it that he is planning to set 

 out a thousand plants, in the Arboretum. It will he in 

 commerce within a. few years, too, as many thousand 

 seeds sent from Korea by -Mr. Wilson when he was there 

 last have been distributed, both in this country and 

 abroad. About five years is required for the plants 

 to reach flowering size. It is predicted that this azalea 

 will presently become a well known and highly valued 

 plant in the gardens of the United States, as well as 

 those of Kuropi'. Prof. Sargent says: 



Rhododendron (Azalea) Schlippenbachii is a shrub 

 which on the wind-swept, grass-covered cliffs of the 

 Korean coast rises only a few inches above the surface 

 of the ground, but in the forests of the north is a shrub 

 twelve or fifteen high with a tail, stout stem. The 

 Leaves of this Azalea are clustered at the ends of the 

 branches, and are broadest at the apex; they are larger 

 than those of most Azaleas, becoming sometimes three 

 inches long and an inch or an inch and a half wide. 

 The flowers, which appear before the leaves, are in clus- 

 ters, pale pink with dark spots at the base of the upper 

 three lobes of the corolla, and three inches in diameter. 

 There can be little doubt of the hardiness of this Azalea; 

 in northern Korea it grows to its largest size wdiere the 

 thermometer falls to 30 degrees below zero Fahrenheit 

 and a freezing temperature is not uncommon in August. 

 In the Arboretum the flower-buds were not injured by 

 the cold winter of 1917-18 on plants growing in an 

 exposed position. 



Although known to Russian botanists as long ago as 



L870 this plant does not appear to have attracted the 

 attention of western gardeners until 1892 when the l.'tc 

 .1. II. Yeitch found a plant growing in a nurserj in 

 Tokyo and sent it to England. In the edition of the 

 ( aialogue of the Yokohama Nursery Company, of 1901, 

 Azalea Schlippenbachii appeared, and at about this time 

 it was imported by Mr. Thomas Proctor and planted in 

 his garden in Topsfield, Mass., where the plants are still 

 growing. These are the oldest and largest in the United 

 States, for the Arboretum plants were raised here from 

 seeds brought home by Mr. J. G. Jack from Korea. 



R. Schlippenbachii, although it has remained ex- 

 ceedingly rare in western gardens, will probably be much 

 better known in a few years, for in the autumn of 1917 

 Mr. Wilson sent from Korea a large quantity of the seeds 

 to the Arboretum. These were distributed among the 

 best gardeners in the United States and in Europe, and 

 as several thousand seedlings have been raised in the 

 Arboretum nurseries, there seems now to be no reason 

 why this beautiful plant should not become one of the 

 chief beauties of spring gardens in regions too cold for 

 the successful cultivation of any other Azalea with such 

 large and beautiful flowers. 



/,'. poukhtmense is another Korean azalea which is 

 almost equally as fine and a little better known, at least 

 among Arboretum visitors. It is a smaller plant, rarely 

 growing more than three feet high on the Pine-covered 

 mountain slopes of the central part of the peninsula. 

 It was first raised at the Arboretum from seeds also 

 brought home by Mr. Jack, and its beautiful rose-lilac, 

 fragrant flowers have been freely produced here now 

 every spring for several years. As it grows in the Ar- 

 boretum this Azalea is a low, broad, round-topped shrub 

 with its lower branches close to the ground. Roots are 

 produced by such branches and would, if cut off and 

 planted, probably soon produce flowering plants. 

 Rhododendron poukhemense, although practically un- 

 known as a garden plant beyond the limits of the Ar- 

 boretum, deserves a place in all New England collections. 



Azalea Poukhanense at the Arnold Akboretum. 



