There is a trend in garden design to favour foliage plants, that is plants with colourful leaves. Where as flowering plants have a season of colour – often fairly short – foliage plants add colour and texture over many months and year round if they are evergreen.
Silver and grey foliage in the garden
Not all coloured foliage is bold or bright. Silver and grey leaves add subtle tones to gardens and containers and act as a foil for stronger colours from both flowers and other foliage. To get the most from silver or grey leafed plants, combine them with other foliage plants or as a backdrop for flowers.
One of the most striking silver plants is the aptly named Dichondra argentea ‘Silver Falls’. This plant produces a cascade of round silver leaves on long trailing stems. It is striking year round as a ground cover or spill over plant and ideal to grow to edge containers or drape from a hanging basket. It can spread across or drape down 1−1.5m and grows in sun or part shade.
Tolerant of extremes
Silver and grey leaves are often an indication of plants that are heat and drought tolerant. This is because the leaf colour may arise from adaptations to reduce water loss (known in botanical terms as ‘transpiration’). This means the plant is less likely to wilt or collapse when water is scarce. Grey or silver leaves that have a soft feel may be clad in fine hairs that protect the leaves from the sun’s rays as well as reducing water loss. Hairy grey or silver leaves are also found on plants that grow in other harsh environments such as beside the sea or in cold mountain zones.
Some of the most widely grown silver or grey leafed plants are trailing plants that are native to Mediterranean climate zones or that grow near the sea, such as snow-in-summer (Cerastium tomentosum), which forms a dense mat of small silver grey leaves. In summer it is covered with tiny white flowers, which give it its descriptive common name. Plant snow-in-summer beside a path, brick edging or to gently cover and soften edges in a rockery planting. It spreads 60−90cm across. To get the best from this plant, grow it in full sun with well-drained soil. Clip after flowering.
Also with furry or felty silver grey leaves and spreading growth habit is lambs tongue (Stachys byzantina), which can spread 60cm across.
Many succulents are also grey and silver and have adaptations to help the plants survive climate extremes. Good examples of silver or grey succulents include many sedum, crassula, echeveria and kalanchoe varieties.
Tall growing silver and grey foliage plants
Silver and grey leaves are not restricted to low-growing plants. Lavenders are small shrubs that provide silver or grey leaves for a year round display even when they are not in bloom. Lavenders can be grown as a hedge or used as an accent plant in a garden or container. There are also compact dwarf forms growing under 30cm.
Lavenders prefer a slightly alkaline soil so dig in lime prior to planting. They need full sun and good drainage. In humid climates lavenders may be short-lived. To keep in shape, prune after flowering.
Other taller growing silver or grey foliage shrubs or perennials include artemesia (particularly the variety ‘Powis Castle’), emu bush and cistus along with some salvias and plectranthus.