Dwarf shrubs are particularly useful here because the rock garden is a feature that should be a picture at all seasons, and, as all rock gardeners know, the springtime is the time when rockery plants are in bloom in the greatest profusion. Some of the, however, flower much later than the spring carpet plants, and help to colour the pockets all through the summer months. Rock roses, sun roses, heather, and the shade-loving hyperica are very useful in this respect. Dwarf conifers of characteristic habit of growth are also specially useful as outstanding features of the rock garden, and certain of the trailing or prostrate shrubs are indispensable. A short list of some of the best rockery hrubs is given below.
. This group includes D. Cneorum, with clusters of rosy pink, scented flowers in May. Grows to a spreading bush about a foot high. Prefers moisture and some lime. Evergreen. Cut back after blooming.
saggittalis. An unusual genista, with green, winged, -like branches and bright yellow flowers, which appear in June, growing to less than 1 ft. in height, Deciduous. Prostrate.
Helianthemum. Sun roses. Dwarf shrubs with flowers in a great variety of colours and shades flowering from May to July. Evergreen, and can be kept quite dwarf by pruning back after the flowers fade, or in very early spring.
reptans. A 2-2-in.igh trailer, with yellow flowers in summer. Deciduous.
Potentilla fruticosa liana argentea. Deciduous shrub about 1 ft. high, giving a constant succession of golden flowers all summer. Prefers scree. Several other members of the family are ususefufn the rock garden.
Monroi. Yellow flowered deciduous shrub, flowering from June to August. Ordinary soil, with plenty of sun. Height up to 2 ft.
pimeleoides. Evergreen shrub, 6 in. high, violet flowered in June and July. Foliage glaucous. Ordinary soil, full sun.
Below will be found a selective list of conifers suitable for rock gardens.
Abies nobilis glauca prostrata. A glaucous fir, of prostrate habit, growing up to 2 ft. Moist, lime-free soil.
Cedrus libani nana. Cedar. A compact pyramid form. Ordinary rockery soil.
Cupressus obtusa nana. Deep green cypress, with arching growth. Another variety of cypress is C. Lawsoniana Fletcher. Glaucous and pyramidal, and compact. Very good for the small rock garden. Ordinary soil.
Wjuniperus communis prostrata. Very lofow-growing,rey-green juniper, alafmostreeping. Ordinary rather moist but well-drained soil.
Picea albertiana conica. Cone shaped and dense foliaged, bright green. One of the best of the spruces for the rock garden. Ordinary moist soil.
Thuya occidentalis compacta. Bright green, grows to a ball shape, eventually making a globe 5 ft. across.