290 THOR) G AOR DEN 2 As Craw 7a Nis 
JUNE, 1916 
raise these plants from seeds, the only success- 
ful way in which they can be propagated. 
In the absence of these plants and in ig- 
norance of their value and beauty resource is 
made to the so-called Ghent Azaleas—a race of 
enchanting hybrids but short lived, indifferently 
hardy and not suited to the climate of New 
England. As pot plants for forcing purposes 
it is all very well to import them from Europe 
by the ship load but for the embellishment of 
the outdoor garden in the colder parts of this 
country they cannot be recommended. Much 
may be learnt from history in the matter of 
plants as in that of mankind and the outlines 
of the origin of these so-called Ghent Azaleas 
is instructive. In 17388, Peter Collinson in- 
troduced from this country to England R&. 
nudiflorum, Kk. viscosum and It. calendulacewm ; 
in 1793, R. lutewm was introduced from the 
region bordering the Black Sea. This Pontus 
Azalea has fragrant, bright yellow flowers each 
two inches across and its value as a garden 
plant was soon recognized. In a few years a 
great number of hybrids between it and its 
American allies were raised in England. The 
work was soon taken up in Ghent, first by a 
baker named Mortier and afterward by various 
nurserymen of whom Van Houtte was the first 
to raise forms having double flowers. But RK. 
luteum came from a warm climate and its in- 
fluence on hybrid offspring has been toward a 
dislike of low temperatures. In a measure this 
explains the lack of success experienced by 
garden lovers of New England with these Ghent 
Azaleas. It is probable that if seeds of Kk. 
lutewm were obtained from its altitudinal 
limits in the Caucasus or from Galicia a 
hardier type would result. “ 
Another class of Rhododendrons much culti- 
vated in Belgium is that known as Mollis 
Azaleas. This has resultel from the inter- 
crossing of R. sinense and R. japonicum with 
various Ghent Azaleas. The class is a very 
beautiful one but is not more hardy in New 
England than the pure Ghents. 
(III) Under the name Tsutsutsi (our third 
section), the Japanese include most of the 
Azaleasknown in Japan and of the three species 
of this section which it is necessary to mention 
here two grow naturally in the Land of the 
Rising Sun and the other in Korea. The most 
important is the scarlet flowered R. Kuempferi 
which was introduced by Professor C. S. Sar- 
gent in 1892, and is one of the most valuable 
shrubs that gardens of eastern North America 
have received from Japan. It is a deciduous 
and perfectly hardy shrub with slender stems 
and twiggy branchlets and grows from three to 
eight feet high. The blossoms open about mid- 
May and the plants are a perfect blaze of color 
for one to two weeks. Where tully exposed to 
the sun the flowers bleach, and to enjoy the full 
beauty of this plant it should be planted in 
artial shade. It is good as a specimen bush 
but it is better when massed. The other Jap- 
anese species I. rhombicum, is a shrub grow- 
ing four to ten feet high with slender rigid 
stems and rich red-purple flowers in small 
clusters. It is perfectly hardy and thrives in 
the open or in partial shade. 
The Korean species (2. poukhanense) is a 
new introduction and was raised in the Arnold 
Arboretum from seeds sent by Mr. J. G. Jack 
from Korea in 1905. In cultivation it is a 
low, much-branched, very compact round- 
headed shrub and perfectly hardy. The dark 
green, oblong, pointed leaves are deciduous and 
the flowers are rosy-mauve or red-violet in 
color and delightfully fragrant. This new 
Azalea flowers very freely and promises to be an 
excellent plant for the open Herder or for the 
rockery. A double flowered form is in cultiva- 
tion under the name of Azalea yodogawa, but 
this plant is very inferior to the type species. 
There are other well known and beautiful 
Azaleas like R. amoenum, R. obtusum and R. 
ledifolium, unfortunately not quite hardy in 
New England and rarer species like R. Schlip- 
penbachii and R. Albrechtii, but we must 
hasten and deal with our second main division. 
HARDY EVERGREENS 
ARDY evergreen Rhododendrons may be 
divided into two groups characterized by 
the nature of the undersurface of the leaves. 
In one the underside of the leaf is more or 
less densely dotted with small, often brownish, 
scale-like glands; in the other it is either 
smooth and green, or more or less hairy (often 
densely felted) or clothed with a pale or dun 
colored crustaceous covering. 
The group with dotted leaves is a very ex- 
tensive one and a great number of species grow 
on the mountains of western China and on the 
Himalaya and three (R. carolinianum, R. 
minus and Rk. lapponicum) are native of east- 
ern North America. All have small or com- 
paratively small leaves but only a very limited 
number have proved to be hardy and amenable 
to cultivation in this country. Many of them 
may be rooted from cuttings but it has been 
found difficult to hybridize them with members 
of other groups. As a garden plant for this 
country, K. carolinianwm is by far the best 
species of this group and is one of the very 
finest of all broad-leaved evergreens hardy in 
Massachusetts. It is a shrub of compact habit 
from four to six feet tall and as much in diam- 
eter, with handsome dark green leaves and is 
very floriferous. The flowers are pale to deep 
ink and are borne in clusters and open and 
ade before the young branches begin to grow 
and therefore are not hidden by them. The 
species is native of high altitudes in the south- 
ern Appalachian region and was formerly con- 
fused with R. minus (better known as R. 
punctatum) which grows in the same region 
but at a lower level. Rhododendron minus is 
an old denizen of gardens and has smaller 
leaves and flowers and a more open habit than 
R. carolinianum and the flower clusters are 
much hidden by the young branches which rise 
high above them. The third native species (R. 
lapponicum) is an alpine plant which also 
grows wild in Europe and has proved a difficult 
subject under cultivation. 
The two dwarf Rhododendrons (R. ferru- 
gineum and R. hirsutum), native of the moun- 
tains of central Kurope are unsatisfactory in 
New England but three hybrids between them 
and R. minus are valuable garden plants in this 
climate. One of these hybrids (R. myrtifo- 
liwm) is between R. hirsutum and R. minus, 
and is a very compact round-topped shrub, from 
two to four feet in height and as much through, 
with neat foliage and small pretty pink flow- 
ers. Another (2. arbutifolium) is a cross be- 
tween Kk. ferrugineum and R. minus and is a 
shrub of open, spreading habit and forms low, 
wide masses. The foliage is handsome but the 
flowers are small and of an unattractive rose 
color and the value of the plant is in its 
ability to cover either sunny or shady banks 
and for this it is admirably adapted. The 
third hybrid is known in gardens as R. Wilsonii 
and is of the same parentage as R. arbutifolium 
which it much resembles in habit and useful- 
ness. From the cold regions of Mandshuria 
and Korea come R. dahuricum and R. mucronu- 
latum, which though they belong to dotted- 
leafed group have deciduous leaves. These 
grow from four to eight feet high and are 
sparsely branched. In the first named the 
flowers are deep rose-purple and pink, and 
rose colored in Rk. mucronulatum. They are 
the earliest of this class to open their flowers 
and in consequence these are often spoilt by 
late frosts in the spring. Other early flowering 
Rhododendrons are R. praecox and its variety 
Karly Gem, whch are the result of crossing the 
Himalayan R&. ciliatwm and R. dahuricum. 
Both are evergreen bushes, much branched and 
compact in habit and have pale to eect pink 
0 
flowers. In favorable seasons when the flowers 
gsc pe late frosts these plants are very beau- 
tiful in spring but unfortunately this rarely 
happens. 
Valuable for the rockery and partial to sun- 
shine are R. racemosum, R. flavidum and R. 
intricatum, three newcomers from China. They 
are twigey plants growing from four to six 
feet high and may be rooted from cuttings. The 
first-named was introduced to Paris about 1890, 
and has pure pink to rose colored flowers. The 
other two were introduced to England by my- 
self in 1904 and one, as its name suggests, has 
pale yellow blossoms while those of R. intri- 
catum are pale violet. These species are very 
floriferous alpine plants with small leaves and 
flowers and of neat and charming habit. 
The only other species of this group that need 
be mentioned is R. micranthum, also trom China, 
which has clusters of minute Ledum-like white 
flowers and small leaves. It is a hardy plant 
of twiggy growth well suited for massing and 
grows from four to six feet tall. 
THE COMMONER GARDEN KINDS 
E now come to the last group, the most 
valuable and desirable of all and the one 
with which most people associate the name Rho- 
dodendron. As met with in gardens and in 
nurseries this eau is mainly of hybrid origin 
and I may preface what follows by an enumer- 
ation of the best varieties which the experience 
of the Arnold Arboretum has found most adapt- 
able to this climate. With red flowers, Atro- 
sanguineum (very early), Charles Dickens, 
H. W. Sargent (late) ; with reddish flowers, 
Caractacus; with rose-colored flowers, Roseum 
elegans, Lady Armstrong; with pink flow- 
ers, Mrs. Charles Sargent, Henrietta Sar- 
gent; with dark purple flowers, Purpureum 
grandiflorum, Purpureum elegans; with light 
purple flowers, Everestianum; with white or 
nearly white flowers, Album elegans, Album 
grandiflorum, Catawbiense album (very early). 
A few more are mentioned later on in the text 
and one or two others, for example, the white 
flowered Madame Carvalho, are promising. 
It will be seen that the number is very small, 
and also it must be pointed out that in the 
Arnold Arboretum these plants occupy a very 
favorable position at the base of a steep slope 
clothed with Hemlock and therefore much pro- 
tected. Had this article been written two or 
three years ago one might have included other 
varieties such as Mrs. H. H. Hunnewell, King 
of the Purples and Delicatissimum, but longer 
experience has proved them less hardy than 
was generally supposed. 
The mild winter of 1914-15 will long be re- 
membered by all lovers of evergreen Rhodo- 
dendrons who endeavor to grow these plants 
outdoors in New England. ‘The effects in gen- 
eral were disastrous though fortunately there 
were exceptions. In some gardens these Rho- 
dodendrons came through exceptionally well, 
in others the mortality was greater than ever 
before. In the Arnold Arboretum varieties con- 
sidered “iron-clad” for twenty years were killed 
outright. No general statement can possibly 
explain these inconsistencies, but the fact out- 
standing is that for New England a tougher 
and more adaptable race of evergreen Rhodo- 
dendrons is absolutely necessary if these plants 
are to occupy in gardens the permanent place 
their beauty merits. Continuing to import 
lants bred and nurtured in alien lands where 
milder climates prevail will not solve the diffi- 
culty. Neither will digging plants from the 
mountains of Pennsylvania, shipping them in 
carload lots to furnish the estate and coaxing 
them in every possible way. This despoiling of 
the countryside is most reprehensible. It is 
vandalism; it is destructive and absolutely op- 
posed to the true spirit of gardening which 
essays to be constructive. None of the easy 
and apparent short cuts will attain the object. 
The problem has to be studied from a very op- 
posite viewpoint and attacked accordingly. 
True horticulturists should welcome it since 
it affords such scope and opportunity to prove 
their worth. 
OUR VITAL NEED 
HT us dig casually into the subject and look 
E the facts squarely in the face and haying 
realized our situation perhaps some one will 
seize the vast opportunity that awaits. What 
American gardens need is a race of evergreen 
Rhododendrons with good foliage, and large and 
bright colored flowers, that is perfectly hardy. 
It is admitted that the few kinds enumerated 
earlier have endured the summer drought, the 
winter cold, and the March sun of New Eng- 
land more or less satisfactorily for a number 
of years but they are still uncertain and own- 
ers breathe freely each May when they find 
the plants still alive and healthy. In Massa- 
chusetts large sums of money have been spent 
on these plants but the results on the whole 
are discouraging and some who have given 
much in time, labor and money in the attempt 
to make this class of Rhododendrons grow suc- 
cessfully are losing or have lost hope. Such 
are the facts of the present-day situation in 
New England and it is pertinent to ask is 
there a remedy or a way out of the difficulty? 
I make bold to say that there is, but it en- 
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