Though much is written
about the various families of Alpines and herbaceous rock plants,
it is seldom that we see attention drawn towards the evergreen and other shrubs which rightly belong to that
part of the garden we are now considering. Not only are we depriving ourselves of a very beautiful and
interesting class of plants, but without shrubs, a rock garden of any size is bound to present a confused or
Rock gardens are often
tame and dull, partly because the foliage and flowers of most Alpines is light in color, but mainly owing to the
fact that in such places there is nothing very definite to hold the eye.
A small group of
comes as a welcome relief, connecting scattered units so that they form one consistent collection and making the
color and form of the smaller rock plants more vivid and distinct by contrast.
The ability to grow
plants is a wasted opportunity if no attempt is made to display them to the fullest advantage.
In the true Alpine
garden our choice of shrubs is necessarily limited, and any we use must be kept on the lower slopes and
approaches. In the mixed rock garden no such restrictions apply, and the heights may be crowned with the fiery
spikes of Gorse and Broom, whilst patches of Rosemary and
Lavender will act as a foil to bright colonies of herbaceous flowers.
The family of
contains several beautiful varieties, many of them especially suited to the rock garden. These delightful shrubs
from mountain and moorland are among the best possible plants for the rough grass and boulder strewn approaches,
and when strongly massed among herbaceous flowers create a welcome note of soft color.
The Alpine Forest
Heath (Erica carnea) is perhaps the hardiest of all, and thrives in practically any class of soil. On the
mountains of Europe
it is snow-covered throughout the
winter, bursting into a multitude of rosy blooms in the early days of spring.
The white variety
should not be forgotten. In warm districts the Tree Heath (E.arborea) may be planted in the lower sections of
the rock garden. A native of Southern Europe and the Canaries, it is found in oak woods, where
its snowy flowers produce a charming effect. In favored spots it reaches the dimensions of a tree, but with us
it is shrub like. Slightly peaty soil suits the Bell Heather (E.tetralix), which flowers freely in late
The Scotch and Dorset
Heaths (E.cinerea and E.ciliaris) are both dwarf kinds, covering the ground with spreading masses of graceful
foliage, and blooming as early as June. The Cornish Heath (E.vagans) and the Common Ling (E.vulgaris) should be
freely planted in rough meadow land or woodland clearing.
Similar to the Heaths,
and equally desirable, are the dwarf Menziesias, tiny Alpine
shrubs with dark tufts of evergreen foliage and clusters of white and rosy bells. M.coerulea, M.empetriformis, and M.polifolia are the
best known, and thrive in the higher ledges in a sandy peat soil. Near these we would place a clump of
Pernettyas (Prickly Heath) whose claim to distinction lies in their large berries in all shades of scarlet and
purple. During the winter their bright appearance is particularly welcome.
The Skimmias, spreading evergreens from
China and Japan, are precious rock garden shrubs, their small size
and adaptability to varying soils render them valuable almost anywhere. Their bright shining leaves are much
like those of the Garland flower (Daphne), whose delicious fragrance rivals that of any other flower. Such gems
as these, far too small and dainty for the mixed shrubbery, and quite unnecessarily grown in pots, are best
placed in the rock garden, where their beauty can be readily appreciated. D.cneorum, with dense terminal umbels
of pink flowers, blooms twice in the year, a small bush but a few inches high, flooding the air with its
The Rock Daphne
(D.rupestris) is a little more difficult to grow, and demands slightly peaty soil with free drainage and
abundant moisture. If a slow grower, it is very free blooming, the whole plant being densely covered with waxy
pink flowers. The old fashioned Mezeron, the joy of cottage gardens, blooms before winter is past,
though, unlike the others, it is
deciduous. A white flowered kind, D.blagayana, is also worthy of notice.
possess great depth and richness of leafage color. Belonging to the mountain ranges of Europe, they are perfectly hardy and well fitted for
association with Alpines and rock plants. R.chamaecistus, an exquisite little shrub, only a few inches high, may be
grown in the highest situations in sandy loam with a slight mixture of peat. It is always found naturally on the
limestone formation, and is impatient of granite soils. Other dwarf kinds are R.myrtifolium, Hybridum, and
Odoratum, the latter a scented variety.
The scarlet flowered
Swiss Rhododendrons (R.ferrugineum and R. hirsutum) known also as Alpine Roses, are of larger growth, and do
best in peaty soil in the lower parts of the rock garden. All the dwarf Rhododendrons except Chamaecistus form
suitable backing plants for bright patches of herbaceous flowers.
Included among these
evergreens is the Partridge Berry (Gaultheria procumbens), with drooping white flowers and winter berries.
It succeeds in sandy soil in partial shade, and is easily increased by division. The other Gaultherias are too
large for any but rock gardens of considerable extent.
Above the groups of
small plants and the hard edge of the topmost rocks, there may be planted those hardy flowering shrubs which are
happy in the sunniest and most exposed positions. An unbroken line of upstanding foliage is not desirable, but bold groups in several places,
with an occasional fringe of overhanging branches. When the rock mound or bank is of only slight elevation we
may in this way screen distant objects from view, and give an air of completeness to the whole
If the upper part of
the rock garden is tenanted only by plants of small stature, it almost appears as though the object of such
dwarfing was to enable an uninterrupted view of scenes beyond. This, however, is unfortunate, a full measure of
beauty is to be found among the Alpines and rock flowers themselves, and a degree of seclusion and privacy is
necessary for their full appreciation.
In the hottest
situations where nothing else will thrive, various kinds of Broom and the double and dwarf Furze may be planted.
It is a mistake to look down on the latter shrub because it grows wild on English commons, there are few more
glorious sights in Nature than a golden sea of Furze beneath a stormy sky.
The double variety is
to be preferred to the single wild kind, lasting longer in bloom and giving more vivid color effects. The dwarf
Ulex nanus flowers at midsummer, and is suitable for small rock gardens. Furze requires regular pruning to keep
it within bounds, and young plants are much easier to establish than older specimens.
The Brooms (Cytisus)
are a beautiful family, from the strong growing C.albus (Portuguese Broom) with its long slender branches
wreathed with white flowers, to the tiny C.ardoini, a miniature Alpine shrub. The Spanish
Broom flowers freely in hot, dry soils, and even our British Broom (C.scoparius) is worth growing on
the wilder outskirts of the rock garden. Of different habit to others of the genus, the Purple Broom trails
along ledges and falls in dense curtains over large boulders.
It is unfortunate that
the Rock Roses (Cistus) are not more hardy, as they are particularly suited to a dry sandy soil in the upper
parts of the rock garden. They
are easily propagated, and a stock of new plants can be raised from time to time, so as to make good any losses.
The flowers last but a single day, but are borne in such profusion that this peculiarity is hardly noticeable.
C.laurifolius and C.cyprius are among the best.
The Genistas (Rock
Broom) are a large family, and contain many varieties for the rock garden. G.germanica is free flowering, and
forms a shrub of moderate dimensions. The double form of G.tinctoria, G.aspalathoides,
G.praecox and G.andreana are among those from which a choice may be made. All the Genistas are readily increased
by seed, are indifferent as to soil, and need transplanting before the roots become too coarse and
Owing to the practice
of crowding the hardy junipers among free growing evergreens in the shrubbery, their value is seldom realised.
When grouped together in the rock garden it will be seen that they are by no means unworthy, the common Savin
(J.sabina) is graceful and has feathery branches. J.prostrata is a good sub-variety.
On warm, sunny banks a
few plants of Lavender and Rosemary. The older bushes look best, the trim balanced form of the young plants
having given place to a freedom of gnarled and twisted branches, lightly flecked with glaucous leaves. Both the
white and blue Lavenders are worth cultivation. Apart from other reasons there is a charm attached to these old
fashioned flowers, which gives them a special claim to our consideration.
Rock shrubs of trailing character are of
the greatest possible value in forming connecting lines between upright groups. The beautiful Rocksprays
(Cotoneaster) drape the larger stones and boulders, and the evergreen kinds are like cheerful garlands on the
cold slopes of the winter rock garden.
The Wall Cotoneaster
(C.microphylla) is quite hardy, and produces a pretty effect with its deep green foliage, white blossoms and
crimson berries. C. horizontalis (Plumed Cotoneaster) is brilliant in autumn, with vivid scarlet berries and
flaming leaves. The Rocksprays are of the easiest culture and do well in almost any soil. With other trailing
shrubs the graceful Muhlenbeckias may be associated, complexa and varia being chosen for preference.