Category Archives: dry shade

Climate Smart Plants for the Garden

verbena_lilacina-blue_oat_grassClimate smart verbena lilacina with blue oat grass

All this talk about “drought tolerant” plants or “water smart” plants is misleading in some ways. What really matters for the success of a plant in your garden is that they are climate smart. You can call the new California garden climate tolerant or climate adapted but it all comes down to the same thing. The plants you choose to grow in your garden should be able to naturally tolerate periods of lower than average water. This doesn’t mean no water during extremely long dry periods. No plant can live without water.

I have two books that I look to for plant ideas when called upon to design a garden in our area. This first was published by East Bay MUD in 2004 and is called ‘Plants and Landscapes for Summer-Dry Climates’. The other book I refer to regularly for ideas and information is ‘California Native Plants for the Garden’. Both are invaluable in these times of water conservation. One of the best tips each of them offer is to garden where you live.

Philadelphus_Felton_Covered_BridgePhiladelphus lewesii near Felton Covered Bridge.

All of us live in a summer-dry climate. Summer-dry gardens are naturally dry for long periods. Knowing which type of plant community you live in can make the difference between success and failure in your garden. Choose the right plant for the right place whether it’s a California native from an area with similar soil and exposure or a plant from another Mediterranean-like climate with growing conditions like yours.

Plant communities have evolved over time with geologic changes in climate, topography and soils. We have several district areas here- mixed evergreen forest, redwood forest, chaparral and sandhills.

If you live in a mixed evergreen forest you garden with trees like coast live oak, tan oak, madrone, bay and buckeye. Understory plants include ceanothus, coffeeberry, hazel and poison oak. Your soil contains serpentine and granite. Many other unthirsty plants like salvias, lavender, santolina, society garlic, giant feather grass, rosemary and rockrose do well here. California natives such as western mock orange (philadelphus lewisii), wild ginger and western sword ferns grow here also.

iris_douglasiana.2048Iris douglasiana (Pacific Coast Iris)

Mixed evergreen forest may also be found along canyon bottoms near streams where big leaf maple, white alder, cottonwood, and western sycamore trees grow. Most plant here grow lush in this deep soil. If you are looking to add something new to your garden here consider giant chain fern, aquilegia, dicentra, Pacific Coast iris and fuchsia-flowering gooseberry.

Chaparral areas are the hottest, driest slopes of these mountains. Dense thickets of manzanita, coyote brush, chamise, coffeeberry, ceanothus, monkey flower and sage are native here. These plants are adapted to little water and often have tiny, thick, waxy, light green or grayish leaves. Soils tend to be rocky and shallow with overlaying rock or a subsoil that is mostly clay. Plants here need to have an extensive root system that reaches widely and deeply for water. If you live here a classic combination would be the spring blooming western redbud and Julia Phelps or Dark Star ceanothus. The combination of magenta and electric blue flowers is unforgettable.

The sandhills near Quail Hollow and Bonny Doon around Martin Rd. are part of an ancient sandy sea floor that was uplifted, eroded and exposed. These sandy soils lack organic matter and nutrients and their white color magnifies the temperature of the summer sun. Unique, native plants like silverleaf manzanita and Ben Lomond wallflower live here. Buckwheat and sticky monkey flower do well here. You might also try growing Lewisia, a pretty little plant native to northern California, thrives in sand and gravel soils with good drainage. This 8″ tall hardy perennial blooms from spring to early summer with extremely showy flower clusters in colors ranging from apricot to pink, rose and bright cherry red. Mulch them with gravel or crushed stone.

callistemon_Little_John.1600callistemon ‘Little John’

Remember right plant-right place. Don’t try to force nature although most gardens do look better with some summer water. Closer to the house we expect a fuller look. Combinations I’m going to try this season include leucospermum paired with blue echium or grey-leafed westringia planted with red-flowering callistemon ‘Little John’.

Will Any Plants Thrive in Dry Shade?

daphne_odora_AureomarginataLooking out the window on a rainy day I forget that spot way back in the shade in the back of the garden will be bone dry come summer. It’s too far away to water conveniently very often with a hose and extending the irrigation for just that one area under the trees in the shade is not practical. I sympathize with clients when they ask me what will grow in a problem area like this. Believe me I know it’s a challenge to bring in some colorful foliage, texture or might I be so bold as to want flowers, too? Take a tip from one who lives in a similar area with the same problems. We’re in this together.

At this time of year when the plums are blooming and the flowering pears are clothed in white blossoms, I want something to extend this look out in the garden. There are several plants that bloom early in dry shade and fortunately they are also deer resistant. Later in the season when soil moisture all but disappears there are other plants that will take over center stage.

But first here are the candidates for early spring color and fragrance in shady gardens.

Fragrant Winter daphne is a handsome evergreen shrub and I especially like the variegated foliage of the variety ‘Aureomarginata’. This small, deer tolerant shrub is good looking year round and does well under the shade of small trees. Although many daphnes are tricky to grow, this one is adaptable and easy to please. During the summer water it as infrequently as the plant will allow. This is usually about once per month. Little or no water in summer will reward you with clusters of fragrant purple flowers that start opening at this time of year. Cut them to bring inside with hellebore for a pretty bouquet.

For fragrant May flowers try daphne burkwoodii ‘Carol Mackie’ which is also easy to grow and requires only occasional water as does daphne transatlantic ‘Summer ‘Ice’. Summer Ice produces sweetly scented flowers for an extraordinarily long time. Flowering begins in early April and can continue as late as November.

Another powerfully fragrant plant for dry shade is commonly known as sweetbox. Sarcococca may not be showy enough to give to your Valentine but the sweetly scented flowers attract hummingbirds and fill the winter garden with a delicious fragrance for weeks starting in January.

Sarcococca ruscifolia forms an upright bushy shrub about 4 feet tall. Another variety called sarcococca hookeriana humilus makes a great ground cover as it rarely exceeds 1 1/2 feet tall. Both plants have dark green leaves, attractive berries and are deer resistant.

helleborus_orientalisHellebores are another winter blooming plant with foliage that looks great, too. I have several varieties including orientalis, argutifolius and foetidus. My Golden Sunrise has large, canary yellow flowers. It’s been blooming for almost a month and will continue for several more weeks. Hellebores are often still flowering during the Christian season of Lent from which they get their common name, Lenten Rose. They are good plants for naturalizing under trees as they are low maintenance, survive with little water and are disease free.OLYMPUS DIGITAL CAMERA

Other plants that bloom at this time of year and require only moderate summer irrigation include Lily-of-the-Valley shrub, clivia, bergenia, mahonia and Pacific Coast iris.

As summer approaches other plants and shrubs will lend their color and texture to the dry shade garden.

Western Wild ginger and Pacific Coast Iris are great ground covers. Good shrubs include deer resistant Osmanthus fragrans or sweet olive. Their white flowers are tiny but powerfully fragrant. Bloom is heaviest in spring and early summer but plants flower sporadically throughout the year. This compact shrub grows at a moderate rate in full sun to partial shade and reaches 10 feet.

Heavenly bamboo are work horses in the shady garden. For a different look try growing nandina filamentosa or Thread-leaf nandina. This evergreen small shrub grows to 2-3 ft tall with very lacy, almost fern-like growth. New foliage is reddish in color and during the fall the leaves turn orange or purplish red. Pinkish-white flowers bloom in clusters in late spring and summer.

There are lots of other shrubs and plants that require only occasion summer water for those shady spots. Email me and I can share even more ideas and suggestions.