The Rock Garden in Spring
With the first breath
of spring bright patches of color will fleck the slopes of the rock garden, and with the lengthening days the
flowers from mountain and hill clothe themselves in summer garb. Quite early, though the keen winds check all
tender vegetation, the Alyssum and
Rock Cresses shake out their banners of purple and gold.
A little later the
Cushion Pinks and snowy Arabis mantle the ledges with rosy blossoms and cascades of white. Now the rock garden
is at its brightest and best. After the barren grayness of winter, when the flowers in garden borders have
scarcely roused themselves from sleep, here is the fullness of life and color.
To which class of
spring flora are we most indebted for the freshness and charm of the rock garden at this season. Surely our
chief cause of thankfulness is to be found in the myriad bulbous plants, the Alpine Irises, the Fritillaries and
Muscari, the Narcissi from mountain pastures, the Snowdrops, Chionodoxa, Snowflakes and Scilla. If rock gardens
were formed for these flowers alone, they would still be worthy of our care, and in this section only bulbous
plants will be considered.
There is no comparison
between the stiff lines of Snowdrops
and Crocuses used so frequently as border edgings, and the same flowers grown in drifts and colonies among the
stones in the rock garden. There is, too, so much variety among these bulbous plants that they may be used with
certainty of success under almost any circumstances.
Before the winter snow
has disappeared, the narrow leaf spikes of Iris Reticulata begin to show above the ground. A small colony of
these flowers produces a beautiful effect in the rock garden. There are several varieties, but none can exceed
the gold and violet splendor of the common Netted Iris. I.r .cyanea is a dwarf blue form, and Purpurea with rich
purple flowers is adapted to warm sheltered corners. The Netted Irises prefer a sandy soil. Grown in bold
clumps, with a groundwork of small Ferns and Mossy Saxifrages, they are among the best of early
Another good dwarf Iris is the Armenian variety, I.bakeriana. It is
much like Reticulata in color, but possesses a distinctive charm in its violet like scent. The Iberian Flag
(I.i berica) is worth growing if only for the singular
beauty of its flowers, the contrast between the purple veined falls, with their sheen of gold, and the violet
pencilled standards is very striking. A warm, well drained soil is necessary, as the Rhizomes decay unless
they are kept dry during the winter.
When planting, the roots should be
surrounded with sand. Iris Cristata (Crested Iris) is a gem for the rock
garden, where it may be grown on sunny ledges with a carpeting of small leaved Alpines. It is only a few
inches high, with broad leaves and pale blue flowers, pencilled with darker markings. In the border, this
exquisite little flag would be lost, but a sunny corner among the rocks offers a charming alternative to growing
it in pots.
Quite the best dwarf
Iris for color effect is I.pumila, which, owing to the size of its flowers,
forms compact masses of violet or pale blue. It grows about six inches high, and from the sturdy character of
its leaf growth, smaller plants are not required to hide the soil.
Most of the early
flowering bulbs produce but few leaves, and therefore look best rising from sheets of dwarf evergreen foliage.
This gives a far better effect than the bare earth, furthermore, in the latter case the blossoms are liable to
be stained during rainy weather.
There are many other
Irises for the rock garden, and it is a never-ending pleasure to experiment with new kinds, supplying suitable
soil and trying the effect of a few bulbs in sunny corners. In addition to those already mentioned, Korolkowi,
rosy-lilac; Balkana, claret and white; and Cengialti, light-blue, should be remembered.
The Narcissi are
another large family of bulbous plants, and to them we owe an everlasting debt of gratitude for many precious
garden pictures. The larger kinds should be naturalised in grass, in woodland vistas, and among choice shrubs,
but the smallest and daintiest varieties are best in the rock garden.
Most of the dwarf
Daffodils prefer a slightly peaty soil, all demand good drainage and sharp sand around the bulbs. A light top
dressing is an incentive to fine bloom, and the delicate kinds, which are liable to injury from spring storms,
should be afforded the warmest and most sheltered positions.
The Hooped Petticoat
Daffodil (N.bulbocodium) is found growing wild in many of the southern European countries. It cannot be considered a hardy variety,
but is worthy of a good position. There are various forms all having rush like leaves. Conspicuus, with large
yellow leaves, is very early, as also is Citrinus, the pale sulphur French kind.
The White Hoop
Petticoat (N.b.monophyllus) is an exquisite variety from Algeria . N.Triandrus (Ganymede's Cup) and its sub-variety
Albus (Angel's Tears) are among the daintiest of the race, but must be carefully sheltered from high winds. The
Rush Jonquil (N.juncifolius) is sweetly scented and not difficult to establish. Though somewhat expensive, a
small clump of the Queen Anne's Jonquil (N.odorus minor) well repays the outlay; on warm soils the pale yellow
double flowers are very striking.
If the rock
garden contains a somewhat moist corner, it would be worth an effort to grow the Cyclamen Daffodil
(N.cyclamineus). The flowers are bright golden, the leaves a vivid green. On peaty soils it would almost
Beside the Narcissi
with their note of creamy yellow, we may place the Scillas and Muscari, giving us a procession of blues from
porcelain to deep indigo. Scillas are of the simplest culture, and when once established merely require an
occasional top dressing.
The best known and
perhaps most beautiful form is the Siberian Scilla (S.sibirica), with flowers a delicate shade of pale blue. It
is a vigorous kind, and the clumps should be divided every few years. On a warm, sandy soil it blooms in
One of the most
delightful ways of growing this Scilla is to plant bold colonies near the margins of Alpine shrubs. The sight of
the blue drifts of flowers escaping from the shelter of dark foliage, and in small colonies descending the rock
slopes, is a spring picture of true charm. Later in the year the Spanish Scilla (S.hispanica) raises its stout
racemes of pendent bells. It is a vigorous kind, and is suitable for naturalising in grass and on the outer flanks of the rock
The white variety (Alba) and Rosea, a pink form, are
also good. For association with choice Alpines it is a trifle too vigorous. S.bifolia, with deep blue flowers,
is the type from which several handsome varieties have been evolved. S.b.taurica, S.b. praecox, flowering very
early, and S.b.alba, are all worth growing.
The Italian Scilla
(S.italica) combines extreme hardiness with brilliant coloring and sweet perfume; in semi-wild places we must
not forget the improved forms of the Woodland Bluebell (S.nutans). Deeper shades among the Scilla blues may be
provided by patches of Grape Hyacinths (Muscari botryoides), which will answer to the same
Other blue flowers are
the Chionodoxas (Glory of the Snow), of which C.luciliae and C.sardensis are desirable. They are at their best
after they have had time to become thoroughly established. The Bulbous Fumitory (Corydalis bulbosa), with
purple blossoms produced in April, may be included in large rock gardens, and in really warm localities the
lovely Chilian bulb Tecophylaea Cyanocrocus gives us a shade of blue hardly to be equalled.
Finally, there are the
Dog's Tooth Violets (Erythronium), with spotted leaves and single, drooping flowers. E.dens-canis, the best
known of the family, thrives in fairly moist sandy soil, but requires a sunny position. The white, tooth like
bulbs should be planted deeply, and division every few years will increase the stock. This variety is of
European origin; others come to us from America . E.giganteum and E.grandiflorum are large, white
flowered, and succeed on slightly peaty soil.
Blue is a color which
in garden pictures calls for contrast. In the spring rock garden, patches and drifts of Snowdrops and Leucojum
should be associated with the Scillas and Muscari.
There are many varieties of Snowdrops, but we need ask nothing better
than Galanthus Elwesii, with its pure, shapely flowers and bright spikes of green leaves. In close, retentive
soils it is disappointing, but is perfectly happy in a mixture of good loam, leaf mould, and sand. Snowdrops
should never be grown in open beds, when such ideal positions as shrubbery and woodland, close turf and, above
all, the rock garden, are available.
The Spring Snowflake
(Leucojum vernum) may be regarded as a large and handsome form of the common Snowdrop. It grows well in similar
positions, and with the same class of soil. In a shady corner, with peaty soil, a clump of Wood Lilies
(Trillium) display their pure white three petalled blossoms above rich shining leaves.
Other small bulbous
plants there are in plenty. The Cyclamens,
Europaeum, Atkinsii and Coum; the Spring Star-flowers (Triteleia) and Fritillaries, Anomatheca and the American
Several of the smaller
varieties of Tulips are commonly recommended as suitable for rock garden planting, such kinds as Greigi,
Sylvestris and Kaufmanniana especially. To my mind, however, they never look well in such positions. Their
stiffness and formality are not in harmony with the wild freedom of mountain plants, and their blaze of color,
glorious though it be, blinds us to the beauty of many a dainty flower and shrub.
The wild Tulips are
delightful in woodland clearings, meadow sides and shrubbery margins, and nothing can exceed the suitability and
charm of old world Tulip gardens, in the Dutch style, a formal arrangement for purely formal flowers. They even
look well in borders, so that it seems unreasonable that they should occupy valuable space in the rock
garden, which affords a home for many plants that will not thrive elsewhere.
The same feeling
applies to the dwarf Liliums, Elegans, Tenuifolium and others. These noble flowers
are so much better suited to border grouping, or the peaty soil among Azaleas and Rhododendrons, that despite
the opinions of others, I never recommend them for the rock garden.