Creating desert landscapes in arid climates is a challenge only if you're trying to emulate gardens found in moister regions. If you're new to gardening in dry climates, consider these ideas for your desert landscape.
Have you ever really looked at the colors of a native desert landscape? Plants with silver and blue foliage predominate. Most need abundant sun, low relative humidity, alkaline to neutral soil, excellent drainage, and soil low in nutrients and organic matter -- all common to arid or desert climates.
Although the leaves appear to be silver or blue, they're actually various shades of green. Tiny surface hairs or scales usually coat the green leaves, keeping the foliage cool by reflecting sunlight up and away from the plant. Other plants may be hairless but grow with a thick, waxy coating that helps retain moisture in the leaves.
You can design a landscape using only plants with silver and blue foliage, or mix them -- they look especially striking when combined with bright or clashing colors such as orange, yellow, and red.
The good news about desert landscape plants with silver and blue foliage is that they often come in an interesting assortment of unusual shapes and textures. Combining these textures and shapes can create a fabulous garden that doesn¿t rely on blooms to carry the day.
Blue foliage trees and shrubs to consider for a desert landscape include: Arizona cypress (Cupressus arizonica) Banana yucca (Yucca baccata) Chisos agave (Agave havardiana) Juniper (Juniperus horizontalis 'Blue Chip') Silver buffaloberry (Shepherdia argentea) Wright acacia (Acacia wrightii) Yellow palo verde (Cercidium microphyllum)
Silver to gray herbaceous plants (plants that die back to the soil at the end of the growing season) include: Beach wormwood (Artemisia stelleriana) Coronado hyssop (Agastache aurantiaca 'Coronado') Curlicue sage (Artemisia versicolor) Dusty miller (Senecio cineraria) Fringed sagebrush (Artemisia frigida) Hairy canary clover (Dorycnium hirsutum) Lamb's-ears (Stachys byzantina) Lavender (Lavandula angustifolia) Licorice plant (Helichrysum petiolare) Pussy-toes (Antennaria dioica) Russian sage (Perovskia atriplicifolia) Silver sage (Salvia argentea) Silver speedwell (Veronica incana) Snow in summer (Cerastium tomentosum)
Blue foliage herbaceous plants include: Blue fescue (Festuca glauca) Blue wild rye (Elymus glaucus) Blue oatgrass (Helictotrichon sempervirens) Blue spruce sedum (Sedum reflexum) Burro's tail (Sedum morganianum) Echeveria spp. Little bluestem (Schizachyrium scoparium 'The Blues') Switchgrass (Panicum virgatum 'Heavy Metal') Sedum spathulifolium 'Cape Blanco'
Desert landscapes are not the best place for lawn grass because of the water requirements, but ornamental grasses, once established, adapt well to dry climates. Their elegant foliage offers four-season interest, and they can serve as screens or as focal points.
Most ornamental grasses are easy to grow and maintain. They tolerate a wide variety of soils, rarely need fertilizer, and have no major pests. Yearly maintenance includes cutting and removing dried foliage before the new growth appears. Every few years, when grasses become too large or the center of the clump dies out, thin or divide them.
As with blue or silver garden plants, you can devote an entire area just to grasses, or you can combine them with herbaceous and woody plants.
When selecting an ornamental grass, select one that is not considered invasive in your region. For example, pampasgrass escaped from gardens now outcompetes native plants in some regions.
Ornamental grasses are classified as warm- or cool-season plants. Warm-season grasses are slower to emerge from dormancy, flower in summer to early fall, and become fully dormant with fall frost. They do better with hot and dry conditions and require fewer divisions than cool-season grasses. Cool-season grasses begin growing in early spring, flower in summer, slow down or go dormant in summer heat, then begin growing again when temperatures cool. They may need more water and frequent division to keep them healthy and vigorous.
Cool-season grasses include: Blue fescue (Festuca glauca) Blue hairgrass (Koeleria glauca) Blue oatgrass ( Helictotrichon sempervirens) Bulbous oatgrass (Arrhenatherum bulbosum) Feather reedgrass (Calamagrostis acutiflora) Quaking grass (Briza media) Tufted fescue (Festuca amethystina and cultivars) Velvetgrass (Holcus mollis 'Albovariegatus')
Warm-season grasses include: Fountaingrass (Pennisetum alopecuroides and P. setaceum) Hare's tailgrass (Lagurus ovatus) Indiangrass (Sorghastrum nutans) Little bluestem (Schizachyrium scoparium) Lymegrass (Elymus arenarius) Mexican feathergrass (Nassella tenuissima) Natalgrass (Rhynchelytrum repens) Ravennagrass (Erianthus ravennae) Rubygrass (Rhynchelytrum nerviglume) Switchgrass (Panicum virgatum)
Desert landscape plants often have interesting or unusual shapes and forms, such as spikes and rosettes, that lend themselves to a sculptural type of design.
Blend your own found objects, boulders, containers, or sculptures with these plants for an artistic, attention-getting desert landscape: Agave selections (Aloe) selections Brittlebush (Encelia) Desert spoon (Dasylirion wheeleri) Fishhook barrel cactus (Ferocactus wislizenii) Rainbow hedgehog cactus (Echinocereus pectinatus) Ephedra selections Jojoba (Simmondsia chinensis) Living stones (Lithops), Manzanita selections (Arctostaphylos) Ocotillo (Fouquieria spendens) Old man (Cephalocereus senilis) Prickly pear (Opuntia) Yucca