Not all shade is created equal.
Some of it comes naturally, the byproduct of towering trees. This shade can multiply with age and appear in gardens where summer sun once glowed.
Other shade comes man-made, blocking the sun on the north side of buildings. Or it creates an oasis of cool under gazebos, pergolas and other structures that shield us from the relentless sun.
In the Sacramento Valley in August, any shade is a premium. Plants may struggle to get light, but we humans (and other creatures) crave shade's instant cool.
Shade also has a dark side. Sun-loving flowers and tomatoes wither in its shadow. As trees mature in older landscapes, shade creeps out over shrubs and annual beds, denying them life- sustaining light. Lawns need a lifeline.
But there's a cool middle ground where plants can be comfortable and people, too. It comes down to knowing which plants to put where.
During summer work days, volunteers congregate in the shade of the gazebo and trees at the UC Davis Arboretum. It's their favorite spot for breaks and work.
"It's always cooler in this garden," said Ellen Zagory, horticulture director for the UC Davis Arboretum. "You walk in and it's 10 degrees cooler instantly."
Superintendent emeritus Warren Roberts gets credit for the gazebo garden's all-white theme. The garden is named for Carolee Shields, the prim and very Victorian wife of the university's co-founder, Judge Peter J. Shields.
Originally, that corner of the campus was a plum and almond orchard. When the arboretum took the parcel over, the gazebo was built as a shade structure for plants.
"The gazebo was one of the first things built out here," Zagory said. "It was dirt field all around."
Eventually, the gazebo garden became a patio to shade people instead of plants. "Warren said, 'It's the only shady place out there why not use it?' " Zagory recalled.
The all-white garden, a popular theme in Victorian times, grew with its surrounding trees.
White also is a perfect choice for shade gardens. White flowers, which may look harsh in full sun, appear brighter and almost luminescent in shade. In late afternoon or early evening, the blooms glow like little flashlights along paths and under trees.
White flowers also tend to be more fragrant, an adaptation to attract pollinators that may not see them in the shade.
The heavy scent of tea olive (Osmanthus) often fills the Shields gazebo garden.
"It's my favorite," said arboretum gardening specialist Theresa Goman. "When it's in bloom, you can smell the osmanthus all over the area. I can be on the other side of the arboretum and smell it. It's mind-blowing."
Shade gardens bloom more in spring when they get more sun before deciduous trees develop their full load of leaves.
The arboretum boasts many shady summer gems. Argentine rain lilies, which look like white crocuses, pop up along paths. Hybrid hollyhocks thrive with a little afternoon sun.
Shade gardens tend to be very low maintenance. Opportunistic weeds have a hard time growing without full sun.
"Shade gardens can have less maintenance than a full sun garden," said Emily Griswold, the arboretum's assistant director of horticulture. "They grow slower, there are fewer flowers, which means less deadheading and pruning."
But some plants especially vines such as honeysuckle and Virginia creeper can thrive in shady spaces. They can take over if not kept in check.
"That's one of my projects," Griswold said as she pruned away around sprinkler heads. "Some plants are hogging all the water."
Because flowers are less prominent, foliage becomes an important feature in shade gardens, Griswold added. Ferns, shade- loving native grasses (such as Carex) and variegated plants add interest without showy flowers.
"The silver variegation can be so interesting," Zagory said as she showed off a variegated privet with silver-edged leaves. "It just glows in the shade."
Along with most of its landscaping, UC Davis is weaning its shade garden off high water use. The gazebo garden and nearby Ruth Risdon Storer Garden of Valley-wise plants have transitioned to more drought-tolerant plants.
Like many backyards, the Storer Garden is getting shadier, too, as its trees grow. With bright-blue flowers, plumbago expands its space in the shady borders.
Native trees such as valley oaks need less water, too. The space under their branches is dry shade and needs plants that can adapt to their same sparse water requirements.
That makes coral bells (Heuchera) a dry shade star.
"I love Opal heuchera," Goman said. "It doesn't get water. It doesn't get any care whatsoever. It's indestructible."
Well-planned shade can make any garden an oasis.
Jorge Loyola, owner of Loyola Landscaping, wanted to spend more time in his small Davis backyard.
"I made it shady it was my choice," he said. "I planted all these trees. Now, it's very shady. I really enjoy having it that way."
Loyola's home has been featured on local garden tours. Beneath a canopy of maples, plums and pistaches, hydrangeas, nandinas, sago palms and ferns make themselves comfortable. Astilbes and impatiens add pops of color. A waterfall creates a cooling melody.
"Those are shade-loving plants," Loyola said. "I've experimented through the years. Some plants have done really well; others don't make it."
In windows of sunshine, dahlias create dramatic displays.
"A couple of spots get full sun," Loyola said. "That's where you can add some color, too."
Unlike sunny lawns that need mowing or full-sun flowerbeds that get crowded by weeds, a shady garden means less work, he said.
"It's really low maintenance and very easy to take care of," Loyola said. "It always looks clean and nice."
The best part about a shade garden in summer is obvious.
"It's a lot cooler!" Loyola said. "I really enjoy it. In summer, you want to be outside. Here, it's comfortable."
KNOW YOUR SHADE
Shade isn't simple. Before planting a garden in existing shade, evaluate your sun and soil situation.
Shade can be solid or dappled. It can move with the sun or pop up seasonably. Shade can be moist or dry or somewhere in between.
Take some notes about where and when your garden gets shade. Then match up plants that can thrive in those conditions.
Shade falls into four categories:
Dappled or light shade: Sunlight moves across the space but never remains full for an extended length of time. It filters through tree branches but still dapples the ground. This often is enough light for even sun-loving plants. It's perfect for succulents, camellias or hydrangeas. In Sacramento, some sun lovers such as geraniums do better in dappled shade that keeps them from burning in full summer sun.
Open shade: Light is bright but there's no direct sun, such as the space under a covered patio or a narrow side yard with northern exposure. Look for plants that like partial shade such as fuchsias and begonias.
Medium shade: This is the space under small trees or on the north side of buildings. Shade lovers thrive here; others won't grow. Think of plants that thrive in the forest or jungle. It's a great spot for azaleas, ferns, hostas, hellebores, ginger, caladiums and coleus.
Deep or full shade: All sunlight is blocked, such as under large evergreen trees or in a narrow garden area blocked by buildings or fences. Only the hardiest shade-loving plants such as ivy or moss will grow in this space.
FAVORITES FOR SHADY SPOTS
Here are some favorite plants for shady spots, recommended by the UC Davis Arboretum staff and volunteers:
Flowering maple (Abutilon): This shrub boasts attractive apricot or yellow blooms, an unusual color in shade.
Fuchsia: Upright varieties thrive in shady gardens under small trees. Hanging varieties are perfect for patios.
Hellebore: Nicknamed the Lenten or wood rose, this shade lover blooms in January in deep shade. The glossy foliage is attractive all year.
Coral bells (Heuchera): A must for dry shade, this low-growing perennial requires little care. Foliage looks interesting year-round. In spring and summer, it sprouts arcing stems of little bell-like flowers.
Hydrangea: These shrubs love shady spots. The oakleaf varieties tolerate the high boron content in Davis water.
Pacific iris: These natives (such as hybrid Canyon Snow) offer showy flowers in partial shade with little or no care.
Soap plant or amole: Used by local Indians to make soap, this California native thrives in the dry shade under oaks where it can get dappled sun.
Stock (Matthiola incana): This popular spring flower actually appreciates the cool of summer shade and can bloom in partial shade. The blue-gray foliage looks good year round.