A silver- (or gray- or blue-) leaved plant is like a refreshing splash of moonlight in the garden. Its ghostly foliage deepens and enriches the pinks and blues and whites of phlox, campanulas, delphiniums, and other neighboring plants, and enlivens the varied hues of their leaves. Used individually, silver-leaved plants are gleaming exclamation points in a sea of green. Massed, they form a silvery sea of their own, altering the whole feel of the landscape.
Most silver-leaved plants come from dry, sunny habitats, and their presence suggests something Mediterranean or alpine. They look right at home among stones, whether in a rock garden or a formal terrace. Many are also fuzzy, adding to the tactile texture of a planting. They invite viewers in closer, for a touch.
Among the most valuable of the silvery set are the few that favor shade. Two species of hosta are undoubtedly the queens of this tribe. Hosta sieboldiana has contributed numerous outstanding varieties and hybrids, including some of the most magnificent plants for shady gardens. The prototypical sieboldiana hybrid, ‘Elegans’, brandishes foot-wide, frosty, blue-gray leaves, creased with deep, curving veins. Where happy, it matures into a majestic, 3-foot tall specimen. Several even more immense blue-leaved hostas have followed in its wake, including ‘Blue Mammoth’ and ‘Blue Angel’. All produce steeples of lavender or white flowers in late spring and early summer.
On a smaller scale (but literally in a similar vein) are the numerous hybrids of Hosta tokudama and its relatives, characterized by heavily veined and puckered, steely-blue leaves. Among the most popular is ‘Blue Cadet’, which makes foot-tall hummocks of pointed leaves, topped in late summer by pale lavender flowers. ‘Love Pat’ bears cupped, puckered leaves in 2-foot mounds, punctuated by early-summer spikes of pale lilac blooms. All blue-leaved hostas appreciate a moist, humus-rich soil (amend sandy or heavy soils with a good compost such as Fafard® Premium Natural & Organic Compost).
A few ferns contribute silver to shady areas of the garden (and pair beautifully with hostas). The classic example is Athyrium niponicum var. pictum, whose feathery, 2-foot fronds are brushed with pewter. Their maroon-flushed stems complete the picture.
Gray, blue, and silver foliage is much easier to come by in sun. The extensive list of sun-loving perennials in this color range includes the following.
- Selections and hybrids of the yarrow hybrid Achillea x taygetea. Plates of yellow flowers arise from ferny, pungently scented foliage in early summer. Perennial favorite ‘Moonshine’ bears lemon-yellow flowers on 2-foot stems. Somewhat brassier blooms crown the 3-foot stems of ‘Coronation Gold’.
- Several species and hybrids of Artemisia. Cultivars of Artemisia ludoviciana such as ‘Silver King’ and ‘Silver Queen’ spread rapidly into expansive, 2- to 3-foot-tall clumps of finely textured, silver-gray foliage. In contrast, the justly popular ‘Silver Mound’ forms well-behaved, one-foot domes of silky, filigreed leaves. It prefers a soil that’s not too moist or fertile, melting out in unfavorable sites (particularly in hot humid weather).
- Any number of Dianthus, such as cottage pink (Dianthus x allwoodii), cheddar pink (Dianthus gratianopolitanus), and grass pink (Dianthus plumarius). All are prized for their early-summer bounty of fringed, red to white, clove-scented flowers, presented above low, fine cushions of narrow, waxy, dusted leaves.
- Sea hollies (Eryngium spp.). Bristling clumps of jagged, lobed, often spiny leaves give rise to thimble-like clusters of blue to silver flowers ringed by bold, spiky collars of pointed bracts. The architectural biennial Eryngium giganteum makes a striking subject for cottage gardens and other areas where it can self sow. Most sea hollies bloom in early to mid-summer.
- Russian sage (Perovskia atriplicifolia and hybrids), a shrubby perennial producing tall, hazy spikes of lavender flowers in summer on upright woody stems with small felted leaves.
- Several salvias, most notably the short-lived perennial Salvia argentea. Its large rounded basal leaves are thickly (and irresistibly) felted with silver.
- The long-time fuzzy favorite Stachys byzantina, affectionately (and appropriately) known as lamb’s ear. Grown primarily for its mats of felted, silvery, tongue-shaped leaves, it comes in various sizes and guises, including a cultivar (‘Silver Carpet’) that lacks the usual furry-stemmed spikes of purplish flowers.
Among the many notable silver-leaved shrubs and trees are lead plant (Amorpha canescens), butterfly bush (Buddleia spp.), silver-leaf hydrangea (Hydrangea radiata), creeping willow (Salix repens var. argentea), dusty zenobia (Zenobia pulverulenta), silver fir (Abies concolor), blue Atlas cedar (Cedrus atlantica ‘Glauca’), willow-leaf pear (Pyrus salicifolia), and white spruce (Picea engelmannii). There’s something in silver for every garden.