RHODODENDRON 



RHODODENDRON 



2935 



sible of this material into the ground, reserving a part 

 for the summer mulch. Shelter the tops with evergreen 

 boughs, the butts driven into the earth a foot or more; 

 in windy positions a temporary board fence is useful. 



Experience at Rochester, New York (John Dunbar). 

 About fourteen years ago, rhododendrons were planted 

 in the Rochester City Parks in beds excavated to a 

 depth of 2 to 2 J^ feet (sandy soil containing lime re- 

 moved), and filled with humus or soil of a peaty nature 

 from an adjacent swamp. Cow-manure was mixed 

 liberally in the surface. Rhododendrons planted in this 

 preparation began to root immediately, grew with 

 vigor, and flowered splendidly. About 20,000 square 

 feet have been planted to rhododendrons in this way 

 with unfailing success. A %-inch-pipe water-system is 

 connected with all of the beds, with faucets at con- 

 venient points, and the plants are thoroughly watered 

 in the growing season, and are never permitted to enter 

 the winter with dry roots. The natural drainage is 

 perfect. Rhododendrons will not tolerate stagnant 

 moisture at their roots. They are thoroughly protected 

 by the lay of the land from the west, northwest, and 

 north winds, but are completely exposed to the south, 

 summer and winter, and with the exception of a heavy 

 mulching of leaves, spread over the beds in the autumn, 

 they receive no other protection. The lace-fly became 

 a very serious pest some years ago. The colonies of 

 nymphs feed on the under side of the leaves and the 

 foliage presents a sickly yellow appearance, as if 

 attacked by red-spider. This is promptly destroyed 

 and kept under control by two sprayings of Ivory soap 

 during the growing season, using it in the proportion of 

 five bars of soap to one hundred gallons of water. 



The following are hardy at Rochester in a normal winter: 

 Catau-biense, Catawbiense album, Anna Parsons, Album elcgans. 

 Album grandiflorum, Alexander Dancer, Amarantinora, Atrosan- 

 guinea. Bertha Parsons, Boule de Neige, Caractacus, Charles Dickens, 

 Csmtlescens, Daisy Rand, Delicatissimum, Dr. Torrey, Edward S. 

 Rand, Ererestianum, F. D. Godman, F. L. Ames, Flushing, General 

 Grant, Glennyanum, Guido, Henrietta Sargent, Henry Probasco, H. 

 W. Sargent, Ignatius Sargent, J. R. Trumpy, Kissena, Kettledrum, 

 Lady Armstrong, Macranthum, Maximum, Maximum superbum. 

 Maximum Wellsianum, Mrs. C. S. Sargent, Mrs. Harry Ingersoll, 

 Mrs. Henry S. Hunnewett, Mrs. Milner, Old Port, President Lincoln, 

 President Roosevelt, Roseum pictum, Roseum elegans, Samuel B. 

 Parsons, Scipio, Senator Charles Sumner, Sherwoodianum. 



The following are liable to severe injury in a very cold winter: 

 Blandyanum, Beauty of Surrey, Charles S. Sargent, Charles Bagelay, 

 Giganteum, Hannibal, H. H. Hunnewell, James Bateman, James 

 Macintosh, J. Marshall Brooks, John Waterer, Lady Clermont, Lady 

 Gray Egerton, Madame Carvalho, Meteor, Marchioness of Lans- 

 downe, Mrs. John Glutton, Ralph Sounders, Rosabel, Stella, The Queen. 



The following species and hybrids are hardy: R. arbutifolium, 

 campanulatum, caucasicum pictum, carolinianum, dahuricum, ferru- 

 gineum, hirsutum, Metternichii, mucronulatum, myrtifolium, Smir- 

 notii. 



Hardy deciduous azaleas. 



These include the species of the sections Pentathera 

 and Rhodora and some of the section Tsutsutsi, and the 

 hybrids known as Ghent azaleas. Most of them are 

 hardy, but in the North and in exposed situations a 

 protection with brush, hay, or mats should be given in 

 winter, to protect the flower buds from sudden changes 

 of temperature. 



In the open, the flowering period of hardy azaleas 

 extends from April to July. First comes R. canadense, 

 R. rhombicum, and R. Vaseyi; then R. nudiflorum and 

 R. japonicum, followed by R. luteum and R. calendu- 

 laceum and nearly at the same time, R. Schlippenbachii 

 and R. Albrechtii; somewhat later, R. occidentals, and 

 last, R. arborescens and R. viscosum. One of the most 

 beautiful is the American R. calendulaceum, which is 

 hardly surpassed in the brilliancy and abundance of its 

 flowers by any of the Ghent hybrids. There may also 

 be mentioned the few species of true rhododendrons 

 with deciduous foliage, as R. mucronulatum and R. 

 dahuricum, which are the very earliest to bloom, and 

 the hardy deciduous Indian azaleas, as R. poukhanense 

 and R. Kaernpferi, which flower with R. Vaseyi and R. 

 nudiflorum. Azaleas are easy to transplant, either in 



186 



early spring or in early autumn, when the year's growth 

 has ripened. If desired, they may be planted for decora- 

 tive purposes in early spring, in beds, without injuring 

 the abundance or brilliancy of the flower, and after- 

 ward removed to give space for other decorative plants, 

 and planted carefully in nursery beds, where they 

 remain till next spring ; and so on every year. Especially 

 the hybrids and varieties of R. japonicum (Azalea 

 mottis) are often and easily forced for winter-flowering. 

 If intended for early forcing, they should be grown in 

 pots, and care taken to allow them to finish their 

 growth as early as possible; for later forcing, after 

 Christmas, they may be potted in fall, or even just 

 before bringing them into the forcing-house. With a 

 temperature of 50 to 55 at night, they will bloom in 

 about six weeks. The Ghent azaleas are grown in great 

 quantities in the Low Countries and in Germany for ex- 

 port to America ; it is usually more profitable to buy this 

 stock each fall than to attempt to raise it in this country, 

 where labor is high-priced and the climate dry and hot. 



Propagation is usually by seeds sown in early spring 

 in frames or pans, in sandy peat, without covering, and 

 kept moist and shady. When the seedlings appear they 

 should have air and a daily syringing. In autumn they 

 are transplanted into boxes or frames, in sandy, peaty 

 soil. The seeds germinate very readily sown in cut 

 sphagnum, but ought to be pricked into boxes as soon 

 as they can be handled. The second year the seedlings 

 should be planted out in beds, sufficiently wide apart 

 to allow a growth of two years. Long upright branches 

 should be shortened, to secure well-branched plants. 

 The named varieties are grafted on any of the common 

 species, usually by veneer-grafting in autumn in the 

 greenhouse, on potted stock. They may also be 

 increased by cuttings of mature wood 2 to 3 inches long, 

 taken with a heel late in summer, and placed hi sand 

 under glass. Layers usually require two years to root 

 sufficiently; they are made in spring, and the buried part 

 inclosed in moss. 



Many hybrids, known as Ghent azaleas or Mollis 

 hybrids (R. Morteri, Sweet, Azalea Mortieriana, Spae, 

 A. gandavensis) , are in cultivation. They have origi- 

 nated chiefly from crosses of R. sinense, and later R. 

 japonicum, with R. luteum, R. calendulaceum and R. 

 nudiflorum, also hi some cases with R. occidentale and 

 R. viscosum. Some good varieties are the following: 



Single-flowered varieties: AUncans, Admiral de Ruyter, 

 Altaclarense (B.R. 28:27); Anthony Roster, Comte de 

 Corner (R.B. 1:9. F.M. 1879:367); Datnesi (Gt. 

 42:1307); Directeur Charles Baumann, Fragrans (J.H. 

 Ill : 49 : 489) ; Geant des BatoMes, Hilda, Louis HeUebuyck 

 (F.S. 19:2019); Marie Verschaffelt, Morteri, Princesse 

 d'Orange, Sanguinea, Tsarine (R.B. 20:277); Van Dyck, 

 Viscosa floribunda. 



Double-flowered varieties: Arethusa, Bijou de Gand- 

 brugge (F.S. 19:2024); Louis Aime Van Houtte (F.S. 

 19:2022); Madame Mina Van Houtte (F.S. 19:2021); 

 Muritto (R.B. 19:232); Phebe (R.B. 19:232); Raphael 

 de Smet, Viryile (R.B. 19:232. G.W. 15, p. 493). 



Indian azaleas. 



This group contains R. indicum and other species of 

 the section Tsutsutsi and the hybrids of them. They are 

 well-known evergreen shrubs, in the North requiring 

 cultivation in the greenhouse during the winter, but 

 some, as R. Kaernpferi and R. poukhanense, have proved 

 perfectly hardy hi the neighborhood of Boston; also R. 

 ledifolium and R. linearifolium will stand many de- 

 grees of frost hi somewhat sheltered positions. Indian 

 azaleas are rarely increased by seeds, which may be 

 sown hi the greenhouse hi the same way as with the 

 former group. Usually they are propagated by cut- 

 tings or grafting. The cuttings root best when made 

 hi August from half-ripened wood, and placed in sand 

 under a frame, with gentle bottom heat. Choicer varie- 



