r46 



HORTICULTURE. 



June 8, 1907 



time as a surface dressing, and, in America .where 

 such hot spells are so common, a moulding of 

 leaves and decayed manure which will keep the roots 

 from scorching, and. in winter, will serve to protect 

 them from extremely low temperatures. 



CHOICE OF V.\RI1STIES 



As regards what varieties can be u.sed with compara- 

 tive safety, I have great faith in the experience which 

 certain kinds have had and withstood for a period of 

 years, at the Arnold Arboretum. This more especially 

 applies to Boston and the ISTew England section. In 

 other parts, viz., around New York and perhaps more 

 so in Philadelphia, a considerable number of other 

 kinds have been found to stand perfectly well. I am 

 somewhat loth to pul>lish the names of certain kinds, 

 from obvious reasons, but 1 think I can safely give such 

 names as Album Elegans, Everestianum, Charles Dick- 

 ens, II. W. Sargent, and a few others, as having stood 

 for 'so many seasons as to be practically safe, although, 

 110 doubt, in common with many other evergreens, such 

 as the mountain laurel (Ixalmia latifolia), and even 

 the hemlock and white pine, they were found to have 

 .sufEered during the extremely severe weather experi- 

 enced some three years ago in the States. This should 

 not. in my opinion, deter "people from planting again, as 

 the damage done that season proved to be, in many 

 cases, only temporary and the plants recovered during 

 the ensuing summer. 



I have noticed, to my great regret, in many places I 

 have visited, that where hybrids have been planted, 

 although a fair percentage of the proper hardy varie- 

 ties are to be found, yet there is a quite large propor- 

 tion of tender varieties which, in America, are abso- 

 lutely useless except to be treated as tender plants and, 

 as such, to be protected in the winter, and consequently 

 after even an ordinary season, without any great ex- 

 treme of temperature, it is found that many have been 

 injured, the result being that the planter is naturally 

 dissatisfied, and at once comos to the conclusion tliat 

 all rhododendrons are unreliable for garden work, and 

 so either plants some other flowering shrubs in their 

 place, or loavns a l)lank space. Now. this is a great 



pity, and 1 attribute it to the fact that the really hardy 

 varieties being somewhat scarce, some nurserymen, with 

 rather elastic consciences will accept and execute an 

 order, even incorrectly, rather than admit inability to 

 supply. Tlie intending planter sliould be most careful 

 to ask for, and see that he gets those kinds only that 

 have proved to be thoroughly reliable, and also when 

 he has them to see they are planted in the proper 

 position, and I feel sure that under these circumstances 

 the use of the hardy rhododendron with its double effect 

 of flower and evergreen foliage is only just beginning. 

 A few words as to the tender varieties: there are 

 among the hybrids many veiy lovely varieties, which, 

 even if they arc not suited for planting out perma- 

 nently, are so line as to warrant their use in other ways 

 with great effect: such as in tubs and sheltered in the 

 winter. This is done with bay trees in order to give 

 certain effects, and why should it not be done with 

 rhododendrons to give another effect? Large bushes 

 or standards can be procured, and I am of opinion 

 that with a rational treatment tliey would be found very 

 easy plants to handle, and in tliat way the more beauti- 

 ful hybrids can Ijc seen and used in American gardens. 

 Other kinds as, for instance, the E. Pink Pearl which, 

 when first shown in England created almost a sensa- 

 tion in the horticultural world, or the variety Gomer 

 Waterer may be used to very great advantage as pot 

 plants, and fully deserve to be known as well in Amer- 

 ica as with us. The subject of rhododendrons i.-, a very 

 large one, and I do not jiropose to go into any further 

 sides of it. Init T shall look forward to the future greater 

 use of this beautiful evergreen in American gardens and 

 hope that my views may turn out to be correct. I feel 

 siu'e, if the planter insists upon being supplied with the 

 really hardy varieties, he will not be -disappointed, and 

 snore than this he will be- conferring benefits iq)on the 

 lovers of gardens generally. 



^/O'-^XL^yK^^^Tr- 



American Niirsci'y. BiU/sliof, Eiii]hniil. 



The Rhododendron 



SU.MK ItllODODKNDUON IIISTOUY 



John Wilmore of Oldford near Birmingham, Eng- 

 land, who was a most enthusiastic amateur horticulturist 

 some seventy years ago, delighted in nuiking experi- 

 ments with various species of plants in order to produce 

 new and improved varieties. He turned his attention 

 particularly to those families which were the most dif- 

 ficult to hybridize, as for instance the ericas; of these he 

 succeeded in raising the one which bears his name, "Wil- 

 moreana" which is a favorite at the present day. He 

 also used his talents on the rhododendron and assisted 

 my father in his efforts in the same direction with this 

 noble evergreen. 



Taking the Indian species, E. arboreum, it was used 

 t(i ])ollenize several other species which were known to 

 lie quite hardy in Great Britain, especially Catawbiense. 

 I'hc flowers ot arboreum are rich crimson with black, 

 chocolate and red markings in tlie throat of the flower. 

 The object aimed at was to get these colors and pencil- 

 ings into varieties which would stand the British 

 climate. This could only lie effected by raising thou- 

 sands of seedlings and making selections of such as 

 ])romised the desired qualities, namely, various tints of 



the carmine and rose of the arboreum to blend with, or 

 supjilant the lilac of the Catawbiense, but combined with 

 the habit and growth of the latter. It was found that 

 if the arboreum was pollenized with the Catawbiense the 

 seedlings were not hardy, but when the Catawbiense was 

 pollenized by the arboreum the habit of the female 

 parent was maintained, but except in rare cases the color 

 of the flower was not materially changed. 



DIFFICn.TTKS IX THE W.AY OF SUCCKSSFl'L UllODODEX- 

 DRON HYBr.IDlZING 



Crossing and raising seedling rhododendrons is a work 

 of years and is full of interest. The first difliiculty, in 

 the case of using the early and late varieties as parents, 

 is to get them in bloom at the same time; the arboreum 

 being the native of a warm clinuite requires the protec- 

 tion of a hot house, and therefore flowers much before 

 the hardy varieties ; to force the hardy ones does not 

 fully answer the purpo-se of the hybridizer, because forc- 

 ing weakens the growth to some extent, and plants thus 

 treated do not seed so vigorously. To retard the arbor- 

 eum seems the most practical, but this is also attended 

 with sonic froii1)lc; it can be effected, however, by keep- 



