Shady areas in a garden tend to cause a lot of head scratching. These spots often confound gardeners who haven't yet learnedthat many attractive plants thrive in dry shade. Some shade-loving plants have colorful foliage that provides as much delightas a bright flower patch in full sun.
Take a walk through local woodlands and you'll find an abundance of understory plants that are doing well under the oaks, big-leaf maples and California laurel trees, some in deep shade.
Many native plants, including some ferns, are adapted to dry shade. We are fortunate that many non-native plants from regions with dry summers tend to grow well in Napa County without becoming invasive. Also, as our winters become warmer, we can introduce more semi-tropical shade lovers, as long as they are able to get some supplemental water. I keep a bucket in the shower to collect the water until it heats up sufficiently.
The majority of my yard is shaded by large trees and shrubs whose roots are likely reaching deep enough to find groundwater. My neighborhood used to be a seasonal wetland. Now the natural vegetation has given way to acres of asphalt, cement, rooftops and other impervious surfaces. This hardscapecauses the City of Napa to have much higher temperatures than the surrounding rural areas. As a result, I am grateful for the tree and shrub canopies that keep my back and side yards cool.
For the past 25 years, I have experimented with plants that might thrive under both Sierra and coastal redwoods, Japanese maples, a huge Mexican ash, a 30-foot valley oak and mature Japanese viburnums. I have discovered many plants that thrive in shade, and I have “trained” some of them to adapt to dryer summersthan they would encounter in their native habitats.
Many perennial plants tolerate full sun in summer but only in climates much cooler than ours. Here, such plants can do well in partially shaded spots where afternoon temperatures stay cooler.
As someone recently said to me, there are “shades of shade.” Light shifts with the path of the sun. Observe your landscape carefully to see how your shady areas change over the course of a day, season and year. How long does that shady spot under a tree or along a fence stay shady in midsummer? How long does the morning sun provide bright light before switching to deep shade in the afternoon?
The aspiring shade gardener needs to take multiple variables into account when selecting appropriate plants. Deep shade from dawn to dusk in winter may be appropriate for a deciduous shrub, a dormant hosta or Japanese wood grass. Such plants might also tolerate a few hours of direct morning sun in summer but would burn to a crisp if exposed to blazing sun during the hottest months.
A bit of risk-taking can be rewarding when experimenting with shade plantings. Many plants will recover if you correct the situation when you see they don't thrive. I have made it a habit of taking photos throughout the year to document plant growth and health, fruit yields and wildlife visitors. The photossupplement my periodic notes in a garden journal.
In our Napa Valley climate, shady areas might provide as much or more joy to you and your guests (animal and human) as those sunny flower and veggie beds. And you can usually find some plant cultivars that don't mind a sunnier shade of shade under a tree with an open canopy. Maybe they'll get less sun than they're accustomed to, but it's enough.
The key to successful shade gardening is to observe the movement of sunlight throughout the day and throughout the year. Then make mental or written notes, or a visual record, so you can add the right plants to that neglected patch.
The author has provided plant ID for a photo caption (clockwise from upper left);
Fatsia japonica (Japanese aralia)
Aucuba japonica
Chinese tree bamboo (Polystachys vivax)
California cranesbill
Clivia miniata
Impatiens balfourii (poor man's orchid)
Library Talk: Join UC Master Gardeners of Napa County for a talk on “Planning a Cut Flower Garden,” on Thursday, March 6, from 7 pm to 8 pm, via Zoom. This summer, your garden can include beautiful, colorful flowers to cut and bring into your home. Join the UC Master Gardeners of Napa County to learn about the best annuals, bi-annuals and perennials for cutting, along with soil preparation tips, starting seeds indoors, and direct seeding techniques. Click here to register!
Workshop: Join UC Master Gardeners of Napa County for a workshop on “Spring and Summer Vegetables” on Saturday, March 8, from 10 am to noon, at University of California Cooperative Extension, 1710 Soscol Avenue, Suite 4, Napa. Come get your hands dirty in this hands-on vegetable growing workshop. Learn what to plant now and what to plant later when the weather warms. Soil prep, irrigation, seed starting, transplanting and potential problems: we'll cover it all. Click here to register!
Help Desk: The Master Gardener Help Desk is available to answer your garden questions on Mondays and Fridays from 10 am until 1 pm at the University of California Cooperative Extension Office, 1710 Soscol Avenue, Suite 4, Napa. Or send your questions to mastergardeners@countyofnapa.org. Include your name, address, phone number and a brief description of the problem.