POPULAR GARDEN PLANTS. 
493 
borders. They are propagated by division after 
the plants have done flowering, and also from 
cuttings made of the side-shoots formed at the 
end of the summer. These should be set in 
a cold frame, or under a hand-glass in a shady 
border. When rooted they can be planted out 
either in the autumn or early spring. 
The double-flowered varieties do not seed 
easily, and the seedlings are generally inferior. 
The single varieties are better in this respect. 
Fig. 600.—Pyrefchrums. 
The seed should be sown in pans in early 
spring and placed in a cold frame or on a shelf 
in a cool greenhouse, covering them with a pane 
of glass, and shading until they germinate. 
Selection of Sorts. 
Double-flowered. —Alfred, Aphrodite, Duchess of Teck, 
Empress Queen, Ernest, Evelyn, Figaro, King Oscar, 
Lady Kildare, Lenoard Kelvvay, Lord Rosebery, Milton, 
Pericles, Primrose, Princess Beatrice. 
Single-flowered. — Alice, Apollyon, Dorothy Kehvay, 
F. M. Peacock, James Kelway, J. G. Clarke, Lord 
Roberts, Macbeth, Mary Anderson, Millicent, Pascal, 
Princess Irene, Princess Marie, Princess of Wales, Ruth. 
Rhododendron (Hardy)..— Undoubtedly 
the finest and best of hardy evergreens, no 
other genus combining so much variety of 
colour, so much beauty of both flower and 
foliage, with vigour and hardiness. 
The garden Rhododendrons, as distinct from 
the species from which they are derived, are 
quite a modern acquisition. The most import¬ 
ant of the parent species— It. catctwbiense, R. ar- 
boreum, and It. caucasicum —have been introduced 
within the last hundred years. R. ponticum, 
which has also played a part in the production 
of the garden race, was introduced in 1763, but 
does not appear to have been used for hybri¬ 
dizing until long afterwards. Although other 
crosses, accidental or otherwise, had been pre¬ 
viously obtained, the first results which may be 
said to have begun the evolution of the garden 
Rhododendrons, as Ave know them to-day, Avere 
obtained between 1826 and 1835. About this 
period the Himalayan, R. arboreum, introduced 
in 1820, floAvered for the first time under culti¬ 
vation. It is easy to imagine the effect of 
its glorious crimson trusses on people Avho 
had only seen before the comparatively in¬ 
effectual and indeterminate hues of the Euro¬ 
pean and American species then in gardens. 
At any rate, the desire Avas generally felt to 
get some of its vivid colour into the open air 
(for it is, itself, only hardy in very feAv parts 
of the United Kingdom), and it was used 
by several hybridists betAveen the dates 
mentioned. Thus Avere obtained altaclerense 
(arboreum x species unrecorded), Nobleanum 
(arboreum x caucasicum ), Russellianum (arboreum 
x catawbiense), Smithii (arboreum x ponticum). 
These first hybrids, raised from R. arboreum , 
naturally retained some of its tenderness, as 
Avell as its propensity to break into flower 
early in the year. But a beginning had been 
made, and by repeated crossing and selection 
a hardy, later-floAvering race Avas gradually 
evolved, Avhich still retained much of the vivid 
colour of the Himalayan species. In fact, all 
that is red or crimson in the flowers of the 
garden race of Rhododendrons has its origin 
in the “blood” of R. arboreum. In the varieties 
that are most free from any purple tinge, such 
as Michael Waterer and Doncaster, even the 
foliage still bears a strong impress of that 
species. During the years that folloAved the 
first crosses with R. arboreum , several hybridists 
took in hand their improvement; but the most 
noteAvorthy, both as regards the length of 
time over Avhich their work has extended and 
the results obtained, Avere the Waterers of 
Knap Hill and Bagshot. Their labours may, 
indeed, be said to have largely given to the 
great bulk of the garden Rhododendrons of 
the present day their chief distinctive features. 
Whilst the great majority of the varieties 
