Designing a garden that can withstand periods of heat and drought begins with proper plant selection. By choosing plants that have adapted to low-water environments, you’ll ensure that your garden can weather the extremes while still looking full and vibrant.
Drought-Tolerant Plant Traits
Plants that are tolerant of drought conditions have various adaptations to help them survive with less water. Some plants store extra water to use as reserves when times are lean, while others may begin to grow early in spring and go dormant by summer to conserve energy.
How Water Moves Through Plants
Water moves up from the soil into the roots, up the stems, and out through the leaves via transpiration. Unlike human circulatory systems, there is no active pump, and the process is completely passive. The air is drier than the surface of the leaf, which is drier than the stem, which is drier than the root. Drought tolerant plants have developed some clever mechanisms to help minimize water loss.
Many plants have specific structures or physical characteristics to help tolerate drought and reduce evaporation, such as:
- Thin, cylindrical leaves or needles– Big groups of plants like grasses and conifers rely on their small leaves and needles to reduce water loss by creating less surface area for water to escape.
- Thick, waxy foliage – Waxes can act like a sunblock or anti-transpirant on the leaves of plants like Eucalyptus and Sea Holly, and often lend an attractive greyish or white hue to leaves.
- Oils and aromatic compounds – Herbs like Sage, Rosemary, and Thyme all employ aromatic compounds and oil glands to reduce water loss, much to the benefit of noses everywhere.
- Hairy surfaces and feathery leaves – Gaillardia, Russian Sage, and Yarrow all use hairs or feathery leaves to create microclimates on the surface of their leaves that trap water and make them less prone to drying out in the heat.
- Deep roots – Prairie plants like Goldenrod, Echinacea, and many ornamental grasses have extremely long roots that can mine deep into the soil to access water, even during summer when surface water is limited.
Drought-Tolerant Plant Suggestions
Below is a list of plants that tolerate drought conditions well. Learn more about landscaping with low water, called xeriscaping, in our blog Xeriscaping: Gardening with Less Water. Plants native to the Pacific Northwest are noted with (N). If you’d like to learn more about gardening and landscaping with natives, check out our guide on Gardening With Native Plants.
- Madrone (Arbutus menziesii) (N): Grows to 35-45’, slow growing; unusual red bark; evergreen leaves; white bell-shaped flowers; uncommon in retail markets
- Western Redbud (Cercis occidentalis) (N): 10-18’ tall and wide; deciduous; sweet, pink flowers along branches in spring followed by heart-shaped green leaves
- Eastern Redbud (Cercis Canadensis): 25-35’ tall and wide; fast growing; deciduous; pink flowers on bare spring branches followed by heart-shaped green leaves
- Incense Cedar (Calocedrus decurrens) (N): Grows to 75-90’ tall and 10-15’ wide at the base; dense, evergreen, fan-shaped sprays of fragrant foliage; reddish bark with interesting texture
- Deodar Cedar (Cedrus deodora): 40-80’ tall and 40’ wide; fast growing; typically green (some varieties have blue or yellow cast), clustered foliage; soft-looking texture; evergreen
- Ponderosa Pine (Pinus ponderosa) (N): 50-100’ tall and 25-30’ wide; moderate-fast grower; evergreen, stiff green foliage; orange-brown bark
- Eucalyptus (Eucalyptus spp.): Size varies by species; most have silver or grey leaves and gorgeous bark; uncommon in northwest retail markets
- Fig (edible) (Ficus carica): 20’ tall and wide; fast growers; deciduous; unique, large hand-shaped foliage; edible fruit in summer
- Cypress (Cupressus spp.): Size varies by species; evergreen, typically green foliage; tough family of plants!
- Spruce (Picea spp.): Size varies by species (some are native); evergreen, fragrant green foliage
- Silk Tree (Albizia julibrissin): 20-35’ tall and wide; fast growing; deciduous; large airy pink flowers in summer
- Japanese Zelkova (Zelkova serrata): 60’ tall and wide; deciduous, elliptical green foliage has jagged edges; smooth grey bark
- Sweet Bay (Laurus nobilis): 12-14’ tall and wide; slow grower; evergreen, multi-stemmed, fragrant leathery green foliage; culinary uses
- Smoke Bush (Cotinus coggygria): Typically 7-15’ tall and wide; oval foliage colored maroon, purple, green or yellow; billowing puffs of flowers in summer
- Compact Strawberry Bush (Arbutus unedo ‘Compacta’): 8-10’ tall and wide; slow to moderate growing; evergreen; stunning red, peeling bark; oblong, red stemmed dark green leaves; white urn-shaped flowers; yellow (young) and red (mature) fruit (strawberry-like texture) appear at the same time as flowers in winter; fruit is edible, but usually tastes bland—birds love them!
- Crape Myrtle (Lagerstroemia indica): 4-25’ tall and wide (varies by variety); deciduous; attractive peeling bark; late summer flowers of white, pink, or red; fall color; sort of a tree/shrub
- Oregon Myrtle or California Wax Myrtle (Umbellularia californica) (N): 6-15’ tall and wide; evergreen, dark green leaves; suitable as a hedge; tolerant of filtered sun/partial shade
- Rockrose (Cistus spp.): 2-5’ tall and wide; evergreen, attractive foliage is green, silver or greyish (some varieties are wooly); profusion of pink or white flowers spring into early summer
- Manzanita (Arctostaphylos spp.)(some N): Size varies by species (from groundcover to tree-like shrubs); evergreen; crooked branches with smooth red to purple bark; white to pink urn-shaped flowers in late winter to early spring followed by red or brown fruit—birds love them!
- Barberry (Berberis spp.): 1.5-10’ tall and wide (varies by species/variety); most are deciduous, some are evergreen; dense, spiny stems; foliage color varies (red, orange, yellow, purple, green)
- California Lilac (Ceanothus spp.): 1.5-15’ tall and wide (varies by species/variety); generally evergreen, foliage ranges from tiny to big and is variant in green coloration; typically flowers in spring—white, pale blue, powdery blue, deep violet blue color varies by species and variety
- Juniper (Juniperus spp.): Size varies by species and variety; evergreen, green or blue stiff foliage; tough family of plants!
- Oregon Grape (Mahonia aquifolium) (N): 6’ tall and 5’ wide; evergreen, glossy green holly-like foliage; bronzy new growth; purplish winter color; yellow flowers in spring followed by edible bluish-black fruit (birds love them!); tolerant of filtered sun/partial shade to shade
- Escallonia (Escallonia spp.): 2-15’ tall and wide (varies by species); evergreen, glossy dark green foliage; pink or white summer flowers; excellent in coastal conditions
- Silk Tassel (Garrya elliptica) (N): 4-10’ tall and wide; evergreen, elliptical foliage has wavy edges; long, silky, tassel-like flowers appear in winter and persist into spring
- Lavender (Lavendula spp.): Size varies by species and variety; evergreen; fragrant pale to dark purple, pink, or white flowers all summer; culinary uses
- Rosemary (Rosmarinus officinalis): Size varies by variety; evergreen, fragrant green foliage; culinary uses; tolerant of light shade
- Snowberry (Symphoricarpos albus) (N): 2-6’ tall and wide; deciduous, roundish green foliage; pink flowers are followed by white fruit that persists over winter; tolerant of light shade
- Red Flowering Currant (Ribes sanguineum) (N): Grows to 5-12’ tall and wide; fast growing; deciduous, foliage shape resembles that of maples and is dark green; gorgeous drooping pink flowers in spring; tolerant of filtered sun/light shade
- Yew (Taxus spp.): Size varies by species and variety, of which there are many; slow growing; evergreen, dark green foliage; grows in sun or shade
- Western Columbine (Aquilegia formosa) (N): 1.5-3’ tall and 1.5’ wide, lacy green foliage; nodding red and yellow flowers in spring; tolerant of partial shade
- Goldenrod (Solidago) (N): 1.5-3’ tall and 1.5-2’ wide; leafy stems held on woody branches; branching clusters of small, bright yellow flowers in late summer
- Yarrow (Achillea millefolium) (N): Narrow, green or greyish, feathery foliage; flat-topped flower clusters in a range of colors on 1.5-2’ stems; long summer bloom time; classic cut flower for bouquets; attracts pollinators and beneficial insects; deer/rabbit resistant; size varies by cultivar
- Butterfly Weed (Asclepias tuberosa): 3’ tall and 1’ wide; multiple stems hold clusters of bright orange flowers that are irresistible to butterflies!
- Sea Holly (Eryngium amethystiunum): Grows to 2.5’ tall and 1.5’ wide; spiny leaves of medium green; silvery blue stems hold conical bluish-purple flowers in summer
- Blanket Flower (Gaillardia x grandiflora): 2-4’ tall and 1.5’ wide; rough greyish-green foliage; daisy-shaped flowers in red and yellow with orange or maroon band; long summer bloom time
- Coneflower (Echinacea): 1.5-4’ tall and 1.5-2’ wide; daisy-shaped flowers with dome-like centers are held on long, stiff stems above oblong, bristly green, clumping foliage; wide range of flower color; blooms from mid-summer until frost; native to prairies of the Midwest and western plains; excellent cut flower; deer/rabbit resistant
- Red-Hot Poker (Kniphofia spp.): 1.5-5’ tall and 2-3’ wide; dense clumps of grass-like green foliage; torch-shaped flowers borne on bare stems; blossoms open bottom to top and change color as they mature
- Russian Sage (Salvia yangii, previously Perovskia atriplicifolia): 3-4’ tall and wide; woody base gives rise to multiple upright stems covered in grey-green foliage; sprays of small lavender-blue flowers late spring through summer
- Jerusalem Sage (Phlomis fruticosa): Grows to 4’ tall and wide; wooly grey-green leaves; deep yellow ball-shaped flowers along the upper half stems spring through summer (must lightly cut back after each flowering for repeat bloom); quite unique addition to the garden
- Wallflower (Erysimum spp.) and hybrids: Narrow foliage; clusters of 4-petaled flowers (wide range of colors) nearly 12 months of the year
- California Fuchsia (Zauschneria californica): 6”-4’ tall (variety dependent) and 3-4’ wide; upright or arching habit; narrow green leaves, orange to red flowers in summer; hummingbirds can’t resist them!
- Verbena (Verbena bonariensis): 3-6’ tall and 1.5-3’ wide; grown as an annual that readily self-sows (reseeds), green foliage stays low to the ground, tall, airy, branching stems carry small, tubular purple flowers in summer
- Tickseed (Coreopsis grandiflora): 1-2′ tall and 3’ wide; narrow dark green foliage; long slender stems hold daisy-shaped flowers; long summer bloom time
- Sage (Salvia spp.): Size varies by species and variety; green to grey to yellow foliage; all have square stems and whorls of two-lipped flowers along stalks; wide range of flower color; spring to summer bloom time
- Cape Fuchsia (Phygelius spp.): showy African native; 3-4’ tall and wide; dark green, oval leaves with finely toothed edges; vibrant, drooping tubular flowers in a variety of colors; blooms summer to fall; hummingbird magnet; deer/rabbit resistant; not a true fuchsia
- Baby’s Breath (Gypsophila paniculata): Grows to 3’ tall and wide; slender, pointed green foliage on stiff stems; hundreds of tiny white flowers bloom in sprays giving a billowy appearance
- Beardtounge (Penstemon) (N): Bright flower spikes with tubular blooms in spring and summer; attracts bees and hummingbirds; native to North America, several species native to Oregon; best in full sun or light shade with well-draining soil; deer/rabbit resistant; size varies by cultivar
- Beeblossom (Gaura): Durable perennial that thrives in heat; graceful, thin stems produce clouds of pink or white flowers from late summer through fall; attracts butterflies; deer and rabbit resistant; size varies by cultivar
- Catmint (Nepeta): long-blooming; low-maintenance; heat tolerant; resistant to most pests and diseases; deer/rabbit resistant); attracts pollinators; size varies by cultivar
Drought-Tolerant Ornamental Grasses
- California Fescue (Festuca californica) (N): 2-3’ tall and 1-2’ wide; loose clumps of blue-green or blue-grey foliage; airy flowers appear in late spring/early summer
- Tufted Hair Grass (Deschampsia caespitosa) (N): 1-2’ tall and 2’ wide; clumps of dark green, narrow foliage; airy flowers appear in late spring/early summer
- Blue Oat Grass (Helictotrichon sempervirens): 2-3’ tall and wide; semi-evergreen to evergreen, graceful fountain-like clumps of narrow blue-grey foliage; wispy, straw-colored flowers in spring
- Japanese Silver Grass (Miscanthus sinensis): 2-5’ tall and 2-8’ wide (many varieties); broad or narrow clumping leaves in varying shades of green; flowers in summer resemble silky tassels
- Switch Grass (Panicum virgatum): 4-7’ tall and 2-4’ wide; narrow, deep green clumping foliage; slender flower clusters open to airy clouds beginning in mid-summer
- Black Mondo Grass (Ophiopogon planiscapus ‘Nigrescens’): 8” tall and 1’ wide; tufts of narrow foliage that emerges green and quickly turns to black; bell-shaped white or pale purple flowers in summer are followed by black fruit; best in filtered sun or partial shade
- Feather Reed Grass (Calamagrostis x acutiflora ‘Karl Foerster’): 2-3’ tall and somewhat wider; arching, narrow clump of bright green leaves; buff-colored flowers emerge in late spring/early summer and can rise to 6’ tall
- Mexican Feather Grass (Nassella tenuissima)
Drought-Tolerant Groundcover Plants
- Creeping Mahonia (Mahonia repens) (N):Grows to 1’ tall and 3’ wide; evergreen, dull blue-green leaves take on bronzy-purple coloration during fall and winter; mid to late spring clusters of yellow flowers followed by blue berries; tolerant of partial shade
- Oregon Stonecrop (Sedum oreganum) (N): Less than 6” tall and 6”-1’ wide; fleshy green, mat-forming leaves that turn bronzy-purple in fall; bright yellow flowers in summer
- Bearberry or Kinnikinnick (Arctostaphylos uva-ursi) (N)
- Oregon Grape (Mahonia aquifolium) (N): 6’ tall and 5’ wide; evergreen, glossy green holly-like foliage; bronzy new growth; purplish winter color; yellow flowers in spring followed by edible bluish-black fruit (birds love them!)
- Beach Strawberry (Fragaria chiloensis) (N): 6-12” tall and 1-2’ wide; 3-lobed glossy green leaves; white flowers in spring followed by small, red edible fruit; tolerant of part shade
- Creeping Juniper (Juniperus horizontalis): 1’ tall and 2-4’ wide; evergreen, grey-green to bluish foliage
- Lithodora (Lithodora diffusa): 6-12” tall and 2’ wide, evergreen, small deep green leaves; rich indigo blue flowers in spring
- Thyme (Thymus spp.): 3-6” tall and 6”-1’ wide; evergreen, wide variety of foliage color; tiny flowers through summer; culinary uses
- Candytuft (Iberis sempervirens): 1’ tall and 1-2’ wide; evergreen, tiny dark green leaves; abundant white flowers at branch tips in spring and sporadically through summer
- Pinks (Dianthus spp.): Size varies by species and variety; primarily evergreen, grass-like green, blue-green foliage; fragrant flowers of various colors in spring into early summer
- Bearberry Cotoneaster (Cotoneaster dammeri): 8” tall and 10’ wide; woody branches hold small, bright, glossy green foliage; bright red fruit
How to Establish Drought-Tolerant Plants
Getting plants off to a good start by planting in fall or early spring will help provide enough time for roots to grow before the soil gets hot and dry with summer conditions. Even the strongest, most drought-tolerant plants need water to start growing and become acclimated. After root systems are established, plants may not need supplemental water. Your specific watering routine will depend on the plant type, sun exposure, soil type, and other factors.
- New plantings may need to be watered daily or every other day for the first week, but eventually, it’s best to water deeply and allow the top one to two inches to dry out before watering again—more like two to three times each week.
- The second year after planting, most plants will need to be deep watered about once per week.
- Once in their third year, plants are considered generally established, and from then on, may only need occasional, supplemental watering during periods of extreme heat and drought.
Be cautious of overwatering, which can lead to root rot. Many plants that are drought tolerant require well-draining soil and may be prone to rot if grown in excessively wet or regularly irrigated areas. Heavy clay soils tend to hold water and drain slowly, so watch for signs of root rot (wilting or yellow leaves when soil is wet, mushy stems, slow growth) and make sure to avoid overwatering, especially in these conditions.
For more information on creating a drought-tolerant landscape, check out our blog Xeriscaping: Gardening with Less Water.