Foliage Color – In general people think of leaves as being green, but look again. Leaves can be all the colors of the rainbow. In itself, green is paramount in the garden. It is the color that induces calm and tranquillity. It has the ability to heighten pale colors and to tone down bright ones, and a pleasant garden can he created with no other color but green. Gardens created entirely with foliage do have a particular quality of unity and peace but they need not be only green.
Foliage comprises many other colors besides green, for example blues, silvery-greys, yellows, reds and cream and green variegations. Of course, these plants often have colorful flowers as well.
The giants of the blue-leaved plants include Crambe maritima and Thalictrum flavum ssp. glaucum, both of which have hlue-green leaves. Medium-sized blue plants include Euphorbia characias ‘Blue Hills’, a rounded compact dome with blue-green leaves, which grows to 1 m (3 ft).
Rosa glauca is a species rose with glaucous purplish leaves and stems. Lower-growing plants include several good blue grasses, including the evergreen Helicotrichon sempervirens, 38–46 cm (15-18 in) tall, and Festuca glauca, which makes little mounds of blue.
Silvery grey-leaved plants
There is a really lovely selection of silvery-leaved plants available. They complement dark green leaves, as well as flower and foliage colors from deepest purple to pale pink and blue. They include the artemisias, for example Artemisia ‘Powys Castle’, which grows to 1 x 1.8 m (3 x 6 ft) and A. ‘Lambrook Silver’, 1 x 1.2 m (3 x 4 ft). Brachyglottis Dunedin Group ‘Sunshine’ (syn. Senecio ‘Sunshine’) grows to 1 x 1.8 in (3 x 6 ft); Elaeagnus ‘Quicksilver’ has striking narrow silvery leaves and reaches 1 x 1 m (3 x 3 ft).
Smaller silver plants include the curry plant with narrow silver leaves, which grows to 30 cm (11 in). Lamb’s ears forms dense mats of thick woolly grey leaves, 40 x 50 cm (16 x 20 in).
Convolvulus cneorum is a charming, low-growing silver plant with white convolvulus flowers. Artemisia schmidtiana ‘Nana’ grows to 30 x 30 cm (12 x 12 in); cotton lavender has finely dissected woolly leaves and grows to 60 x 60 cm (24 x 24 in). The woolly willow (Salix lanata) is a low, spreading bush for rock gardens, measuring 30 x 30 cm (12 x 12 in).
Red,bronze and purple-leaved plants
Red, bronze and purple leaves can be sensational if carefully placed. The red and bronze colors can complement other plants significantly. They look particularly good with greens and silvers, but may be less successful with variegated and yellow-leaved plants.
Cotinus coggygria ‘Royal Purple’
Cotinus coggygria ‘Royal Purple’ is a splendid shrub with purple leaves, which turn bright red in fall. Berberis ‘Bagatelle’ is a rounded shrub with bronze-purple foliage, often used as a hedge.
Many roses have deep bronze young foliage in spring, which later turns green. Cercis canadensis ‘Forest Pansy’ is a deciduous tree or large shrub with bronze-reddish-purple foliage, which keeps its color all season. lt needs a sheltered, sunny spot and is slow growing but will eventually reach 12 m (40 ft).
Berberis thunbergii ‘Atropurpurea’
The palm-like Cordyline australis ‘Pink Stripe’ has leaves with purplish edges and a rich pink central stripe. lt is not hardy so it should he grown outside only in mild areas or in tubs where it can be brought in for the winter.
Heuchera ‘Palace Purple’ has coppery purple leaves and the leaves of H. ‘Pewter Moon’ are heavily marked with silver. Berberis thunbergii ‘Atropurpurea’, also known as ‘Crimson Pygmy’, is a deciduous berberis with rich purple new foliage. It is good as a colorful low hedge or a rock garden plant.
Heuchera ‘Palace Purple’
Berberis thunbergii ‘Aurea’ has spectacular yellow leaves and makes a rounded bush 1 x 1 m (3 x 3 ft). The Mexican orange blossom is an evergreen shrub with very yellow young growth.
Cornus alba ‘Aurea’ is a deciduous shrub, which grows to about 1.8 m (6 ft) tall. Golden privet (Ligustrum ovalifolium ‘Aureum’) has green leaves with broad bright yellow borders. Hedera helix ‘Buttercup’ is a good bright yellow ivy, which will grow to 2 m (7 ft).