Plants with silver or gray foliage are sterling additions to xeric landscapes.  They're versatile, easy to cultivate and drought tolerant.  They thrive in dry, sunny locations with nitrogen-poor, but well-drained, soils.  Though partial to sandy or gravelly soils, they adapt to heavy clay that has been adequately amended for drainage.  Their most appealing characteristics: soft, velvety or finely haired leaves that invite touching, lacy or feathery leaf structures, and luminous, near-white coloration- are, in fact, the biological adaptations which enable these plants to retard water loss and survive the dry heat of semi-arid environments such as ours.  The pale delicacy of Silvers belie their tough, and occasionally aggressive natures, so don't pamper them!  Given more moisture than needed or overly rich or saturated soils, and they will disappoint: grow leggy, sprawl open, abandon their silvery sheen, turn mushy or develop crown rot and die.  If planted in unamended or compacted clay, their roots will struggle to take hold and they will fail to thrive.  That cautionary bit of advice given, Silvers, as with all new plantings, including drought-tolerant ones, will need extra water to help them get established in their first year.  Even well-established plants may need supplemental irrigation, if allowed, during prolonged drought conditions.

The Silvers are well represented in the large genus, Artemesia, but include two garden familiars: Stachys lanata (bizantina), or Lamb's Ears, and Cerastium tomentosum (Snow in Summer), as well as plants native to the desert southwest, such as Shepherdia argentea (Silver Buffaloberry) and Ceratoides lanata (Winterfat).  Most are hardy perennials, though a few, like Dusty Miller (Senecio cineraria) and Silver Licorice Plant (Helichrysum petiolare) are annuals in our 4b USDA cold hardiness zone.

Beyond their laudable xeric qualities, Silvers can make important contributions to garden structure and design.  A plant's foliage generally outlasts its floral display, and this is especially true for Silvers, since their importance as textural elements generally far exceeds their floral interest.  Choose and place them with consideration to their long term compatibility with your other plantings.  Silver can break up the monotony of green, providing contrast and gentle, but eye-catching accents.  Evergreen Silvers will maintain their focal interest throughout the year.  The light, airy textures of Silvers work well as foils with bolder, heavier foliage forms.  Their neutral tones serve to enhance strong colors - mellowing brighter hues, intensifying deeper ones.  Bright whites are showcased by Silver too, though pastels, having less saturated color, tend to wash out or get lost.

Silvers can be massed together for a quiet, muted foliage effect.  A Silver garden will succeed when plants of similar form and disposition, but differing textural qualities, are combined; for example flowerless Lamb's Ears grouped with Santolina and Silver Speedwell.  (You may want to remove the bright yellow flowers of Santolina before blooming to maintain the cool serenity of this particular combination).  Though used most frequently for their foliage effects, some Silvers, such as Cerastium tomentosum (Snow-in-Summer), or the subshrub, Perovskia atriplicifolia (Russian Sage), are equally valued for their inflorescence.

Silvers are prized for their aromatic and herbal qualities too.  Their pungent scents fill the air around them, becoming even more pronounced when their leaves are brushed against or rubbed between fingers.  In open, rural areas where wildlife is a problem, some Silvers -Russian Sage and Santolina are two - present another asset: they are deer repellants.  (But Pussytoes are not, so shelter them in a more protected spot).

If you want to see some Silvers for yourself, get out and cruise the neighborhoods, take a garden tour, visit a botanical garden, or browse our local garden centers.  Note how Silvers perform in different planting situations, or in landscapes similar to your own.  If you prefer more sedentary research, I recommend "Xeriscape Plant Guide," compiled by Denver Water.  It's a well-organized resource guide, offering detailed information on specific plants as well as attractive botanical drawings and colored photos of its recommended selections, which includes Silvers.  The following list gives you an idea of what's suitable for our locale and offers a few tips for successful growing.  All the plants included below are cold and drought hardy perennials for the Front Range.

*Antennaria rosea (Pussytoes) - diminutive, mat-forming silvery-green foliage; happy in spaces between flagstones; slender stems support clusters of small pink flower bracts appearing in late Spring.  Used as ground cover or in rock gardens.  Try intermixing it with the violet-blooming perennial Thymus serpyllum "Coccineus" (Mother of thyme). A. parvifolia is the dwarf variety, with white blossoms.  Deadhead after blooming to prevent self-seeding or dormancy during dry periods.  Likes it dry, but may need irrigation during prolonged dry spells

*Artemesia "Powis Castle" -fine filigreed foliage grows on woody stems; aromatic; some dieback possible in wet winters; prune back previous year's growth 8-12" in late spring, after foliage starts to emerge.  *A. absenthium "Lambrook Silver" is similar and even more cold hardy.

*Artemesia "Silver Brocade" - resembles Dusty Miller but is cold hardy; appropriately named for its ornately lobed, powdery foliage; grows to 6"; some dieback in wet winters possible, but is easily grown from stem cuttings in spring.

*Artemesia "Valerie Finnis" - similar to more familiar A. ludoviciana "Silver King" (Prairie Sage) but with broader, feathered leaves and less aggressive tendencies; grows in clumps18 to 24" high; glowing silvery-white foliage a striking contrast for burgundies, deep roses, purples, blues and golds.

*Oenothera macrocarpa v. incana "Silver Blade" (Evening Primrose) - waxy, silver-gray foliage grows on trailing stems, 10-12" H; cup-like yellow blossoms from May to Frost; a Plant Select winner for 1999; easily cultivated in well-drained, average garden soil; Companions nicely with A. "Silver Brocade".  (Note: Plant Select is a cooperative program administered by Denver Botanic Gardens and Colorado State University Cooperative Extension.  For more information about this program and a complete listing of its selections, go to web site www.larimer.org/ext then Gardening / Horticulture, then Plant Select.

*Salvia argentea (Silver Sage) - described as "a superlative foliage plant...for the water-smart Garden" in the Plant Select listing for 1997; large, silver-green ruffled leaves covered with silky hairs; stems of white, helmet-shaped flowers grow 2-3' high; tolerant of partial shade but not excess moisture.

*Santolina chamaecyparissus (Lavender Cotton) - aromatic, mounding subshrub with fine, divided leaves and bright yellow button-shaped flowers; 12-18" H; evergreen; may suffer dieback or death in overly-wet soils; suitable for rock gardens, borders, natural landscape settings; shear annually after blooming for more compact appearance.

*Stachys byzantina - "Silver Carpet" is the flowerless variety, but still blooms occasionally; dead-head to prevent self-seeding and sprawl; more tolerant of wet conditions and light shade than other Silvers but avoid over-head watering; remove old foliage in early Spring, soon after new foliage appears.

* Veronica incana (Silver Speedwell):clump-forming pale gray foliage with blue flower spikes; companions nicely with other Silvers; tolerates part shade; grows to 12".

Q: I'm having trouble with plants growing near my walnut tree. Could there be a soil problem?

A: The roots of walnut trees release a chemical into the soil called juglone. They release it through tiny root hairs as far as 50 feet from the trunk, and also through leaves and nut shells. This is how this tree ensures its survival-it kills off the competition for moisture and nutrients. Many plants are sensitive to juglone and will not grow well under their canopy. Other less sensitive plants, will do fine.

Q: I'm told not to plant aspen trees in my yard here in Loveland. Why?

A: Probably because aspen rarely stay healthy at Front Range altitudes. Aspen grow at higher altitudes with cooler temperatures and more moisture. Here on the Front Range, they are stressed making them susceptible to many disease and insect problems such as cytospora canker, foliar diseases, trunk and branch cankers, scale insects, aphids and more. There are a number of small ornamental trees that are better choices for our climate. See Fact Sheet #7.418 - Small Decidious Trees for a information of small trees for the Front Range.

Q:  Can lilacs do well in my xeric garden?

A: Young lilac shrubs require consistent watering, but will become quite drought tolerant once established. For the first 2-3 years, water moderately by hand if necessary. Do not prune-just trim dead wood and remove faded flowers soon after blooming. You will be rewarded with many years of carefree, aromatic flowers needing little supplemental care.

To help save on room in your garden, try using arbors or trellises. Most plants will thrive on the air circulation they will receive.  It will also free up some space for additional plants.

To help choose a color scheme in your garden, visit a local paint store.  They have many paint samples there that you can use in choosing just the right colors for your garden beds.  This can also be done with your child's crayons if you can get the crayons away from them.  Do remember that they don't have to be an exact match in order to work.

It is just as important to keep houseplants away from air conditioner vents as it is heating vents. Both are very drying to the soil as well as the leaves.  Remember to mist your plants to replenish the moisture.

The authors have received training through Colorado State University Cooperative Extension's Master Gardener program and is a Master Gardener volunteer for Larimer County.

Gardening and Insect Fact Sheets are available on-line by clicking HERE.

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This page updated:  June 23, 2003