Drought Tolerant Plants for Low Water Landscapes

Xeriscaping is the practice of landscaping using drought-tolerant plants. The term derives from the Greek word, xeros, meaning "dry," and scape, meaning "scene". Hence, xeriscaping literally means dryscaping, or "dry scene".

There are several reasons why you should consider xeriscaping. First, water is an increasingly valuable resource, and is becoming more and more expensive. Second, even if you don't live in an arid region, using plants that don't need more water than the natural plants in your area do to thrive is a good way to ensure your landscape plan does not create a stress on the natural environment.

You could also look at it this way: if you love a heavy irrigation plant like roses, xeriscaping the rest of your garden allows you more water for your rose beds...you could add a few more roses after you scale back the rest of your water use!

I believe in xeriscaping because it not only protects a valuable natural resource, but also allows for a beautiful garden while still maintaining the integrity of the surrounding natural environment; it enhances what nature has given you without looking artificial and man-made. To that end, I xeriscape as much as possible when I design a garden for someone. In my opinion, it just makes good sense.

The following flowering plants flourish in dry conditions once established. Latin/botanical name given first, then the common name. Varieties are in single quote marks. X marks a hybrid. If the botanical name has been changed, the original is given in italics.

Image to the right is Cercidium 'Desert Museum,' photographed in May, in Woodland Hills, California

Blues/Purples
Agapanthus africanus - Lily of the Nile
Andropogon gerardii - Big Bluestem, Turkeyfoot
Campanula poscharskyana - Serbian Bellflower
Echium species (no common name)
Eremophila decipiens - Emu Bush
Jacaranda mimosifolia - Jacaranda tree
Lavandula species - Lavender
Rosemarinus officinalis - Rosemary
Salvia leucantha - Mexican Bush Sage
Westringia fruticosa - Coast Rosemary (not a true rosemary)

Pinks/Reds
Arctostaphylos species - Manzanita
Amaryllis belladonna - Belladonna Lily, Naked Lady (Brunsvigia rosea)
Anisodontea x hypomandarum - Cape Mallow
Aptenia cordifolia - Red Apple
Cistus species - Rockrose
Galvezia speciosa - Island Bush Snapdragon
Leptospermum scoparium 'Ruby Glow' - New Zealand Tea Tree 'Ruby Glow'
Raphiolepis umbellata - Yeddo Hawthorn
Salvia greggii - Autumn Sage

Yellows
Cercidium species - Palo Verde
(Cercidium 'Desert Museum' is a thornless cultivar)
Fremontodendron species - Flannel Bush (Fremontia)
Genista species - Broom (some are like weeds; choose carefully)
(Cytisus, Spartium)
Parkinsonia aculeata - Mexican Palo Verde

Whites
Cercis occidentalis 'Alba' - Western Redbud 'Alba'
Myrtus communis 'Compacta' - True Myrtle 'Compacta'

Multi-Colored Blooms
Dietes iridioides - African Iris, Fortnight Lily
(white with yellow & purple)
Feijoa sellowiana - Pineapple Guava
(white with pink/red)

Colored leaves
Phormium tenax - New Zealand Flax (wide variety of colors available)

There are two basic categories of lawn grasses, cool-season, and warm-season. (Within those categories are groups of sun and shade grasses, but we're not going to get that detailed here...see your garden center or consult a gardening book.)

Cool-season grasses tend to do well in the winter but don't take well to hot, dry summers. They fare best in the Northwest or anywhere a strong marine influence exists to temper the heat of summer. They will also grow well in parts of the Rocky Mountains where there's a lot of summer rain. Cool-season grasses will grow in other parts of the country, but the need a lot of summer watering, so they're not really drought-tolerant in a hot, mostly dry region.

The subtropical warm-season grasses, on the other hand, fare very well in areas with hot, dry summers, but don't take winter cold well and turn brown. If you want a green lawn year round, you would do well to overseed your warm-season seed with cool-season varieties.

The following grasses are drought-tolerant for their specific zones.

Cool-season Grasses
Agropyron cristatum - Crested Wheatgrass
Festuca rubra - Red Fescue (also in blue-leafed California varieties)
Festuca californica - California Fescue
Festuca elatior - Coarse Fescue (also does well in hotter climates)

Warm-season Grasses
Bouteloua gracilis - Blue Grama
Buchloe dactyloides - Buffalo Grass
Cynodon dactylon - Common Bermuda Grass
Zoysia - Zoysia (sun and shade)

There are several ways to maximize the moisture in your soil and help your plants retain water.

Use drip irrigation and water after sunset once the heat of day has passed. Watering at night helps cut evaporation and gives plants longer to absorb moisture before the heat of day burns it away.

Mulch. It helps cut both evaporation and weeds. Plus, it looks fabulous in most Mediterranean gardens and gives a well-manicured appearance.

Add organic matter (ie. compost, manure mixes, sphagnum/peat moss) to the soil. If you have acid-loving plants, pine needles also make a great planting material and are very easy to come by, if you live in an area with a lot of pine trees. Sphagnum can also acidify the soil, so check your garden book to find out which of your plants like or will tolerate acidic soil.

Plant trees and larger shrubs to create shade.

Use dense plantings and decorative walls to break up airflow/wind.

Use an automatic watering system and low-volume heads. Make sure your sprinkler system and/or tubing are in good repair and working properly. Don't overwater.

Ornamental Grasses
Carex barberae - Santa Barbara Sedge (may need a little summer water)
Festuca glauca - Common Blue Fescue
Muhlenbergia species - Muhly, Deer Grass, Bull Grass (check the species for name, which tends to match color...ie. Pink Muhly)
Nassella tenuissima - Mexican Feather Grass

Ground Covers
Baccharis pilularis 'Twin Peaks' - Dwarf Coyote Brush 'Twin Peaks'
Cotoneaster dammeri - Bearberry Cotoneaster
(Cotoneaster humifusus - v. small flowers and bright berries)

Shrubs
Carissa macrocarpa - Natal Plum (white flowers, yummy fruit!)
Cupressus sempervirens - Italian Cypress
Elaeagnus species (no common name; often called Silverberry)
Mahonia aquifolium - Oregon Grape (not a grape)
Phormium tenax - New Zealand Flax
Prunus caroliniana - Carolina Laurel Cherry

Trees - Deciduous
Cercis occidentalis - Western Redbud

Trees - Evergreen
Brachychiton populneus - Bottle Tree
Cedrus deodara - Deodar Cedar
Eucalyptus pulverulenta - Silver Mountain Gum
Geijera parviflora - Australian Willow
Olea europaea - Olive tree
Pinus canariensis - Canary Island Pine
Quercus agrifolia - Coast Live Oak (needs no supplemental watering after its first 2 dry seasons, once planted)
Quercus ilex - Holly Oak
Quercus suber - Cork Oak
Sequoia sempervirens - Coast Redwood (once established, fog is enough water...till then, it needs moderate regular watering)
Schinus molle - California Pepper Tree

Drought-tolerant plants can go for long periods with little to no water, but that doesn't mean they never need to be watered. You will need to monitor the health of your plants and give them a little extra moisture from time to time, especially new plants that have not yet established themselves in your yard or garden. Please bear in mind when you first install a drought-tolerant plant, that while it will live through long dry periods later, you must still water it to begin with. The planting process is stressful to all plants, which are going from a nice, safe container into what is effectively the wild outdoors. They need love and a little help when you first plant them.

You will need to give your drought-tolerant plant regular water (even if it's only light watering) until it establishes a healthy root system. Some of the factors influencing how long that takes are the time of year you install the plant, where it is in its growth cycle, and the type of soil it's in. For instance, a plant that generally exhibits new growth in the spring won't root as quickly in fall or winter as it will in spring. And all plants need some time to adjust to their new soil homes.

Plants will generally need an entire growing season until they are established in their new habitat and can be treated as "independent adults." That's about 3 - 6 months, depending on when you choose to install them. You will want to take extra care and water them well the first week, to help relieve the stress of transplanting. If you aren't sure how long your new plant(s) will take to root, or you want to know exactly how much water you need to give them at first, ask the nursery employee helping you. He or she works with all the plants in the nursery every day and can give you any extra advice you might need. They want your plants to be as happy as you do, both because they love plants and because they want you to be a satisfied customer. Especially if you are landscaping your yard on your own, your nursery person can be your best professional pal -
don't be afraid to ask questions! Remember, plants are living things, and you are their champion and caregiver. :)