By Susan Corey-McAlpine
UCCE Master Gardener of El Dorado County
“Fall has always been my favorite season — the time when everything bursts with its last beauty, as if nature had been saving up all year for the grand finale.” — Lauren DeStefano, “Wither”
It’s very true that our Western Slope fall color can rival the East Coast: think of Highway 50 with its Chinese pistache (Pistacia chinensis), the dark russet of dogwood leaves, the gold of valley oaks and, maybe in your own backyard, the purple bronze of heavenly bamboo or a sweet gum tree (Liquidambar), which can show off green, gold and bronze leaves on the same fall afternoon.
Incorporating fall color into your backyard requires your attention twice each year: You can best take note of trees and shrubs in their fall glory but the economical season to plant that color is right now, when nurseries carry bare-root or potted stock. Fall is the time to look for especially breathtaking color as well as judge whether the size, shape and required exposure of the adult tree will work for you; spring is the time to carefully shop for that same tree and plant it in an area which mimics the location where first you admired the adult.
Planting exactly what you want requires a little research. Let’s look at Chinese pistache as an example. Both female and male pistache are hardy, can withstand harsh conditions and poor quality soils and grow to a good size, but the female tree sheds less-than-desirable berries. The University of California, Davis, has successfully hybridized a male pistache, the “Keith Davies” variety, which has riper color and no berries.
Chinese pistache will thrive on the open freeway hillsides in moderately alkaline soils, but if your planting site is shaded, perhaps with lovely filtered sun under oak trees, choose a dogwood instead. The Pacific or Western Dogwood (Cornus nuttallii) has leaves that turn yellow, pink and red in the fall, is happiest under a canopy, mulched heavily, and in an acidic soil.
There are maples and flowering pears and plums now available in bare-root stock; one of my favorite trees is a hardy, purple-leaved plum that has survived two branch-breaking snowfalls and still has an attractive shape. Our red maple stands at 40 feet and has delicately pointed, bright red leaves in the fall. Smaller spaces in our shade garden shelter potted Japanese maples, also sporting beautiful red leaves.
A predominant concern when planting new trees, actually planting anything new this year, is the undeniable fact of drought. You will be watering new plantings more often and deeper than established plantings, so you might be seeking drought-tolerance and fall color in the same tree or shrub. Consider a Japanese crape myrtle (Lagerstroemia) with its autumnal show of yellow, or the hybrid, “Biloxi,” which has dark red leaves in the fall. These crape myrtles are also resistant to powdery mildew which is a nice plus. The pistache, Japanese maples, most deciduous oaks, red maple, some dogwoods and barberry are considered “drought-tolerant.” The evergreen heavenly bamboo (Nandina domestica) is a beautifully lacy shrub that not only has fall and winter color, but does quite well in semi-drought conditions.
Master Gardener Kit Smith, in a 2011 article on “Trees to Avoid Planting,” recommends against planting cottonwoods, aspens and birch, all of which have gorgeous fall color. The first two have aggressive surface roots that might not only crowd out other plants but also damage sewer lines, driveways and sidewalks. The birch is a “greedy consumer of water.” It’s recommended that you ask your nursery about a plant’s water consumption before you buy, both to estimate water savings and to avoid planting a moisture-loving plant in a setting of drought-tolerant plants.
Lots of thinking before you plant? Maybe so, but you will be rewarded with that joyous first glimpse of fall, the grand finale of bright color in a perfectly situated and healthy tree.
Master Gardeners are available to answer home gardening questions Tuesday through Friday, 9 a.m. to noon, by calling (530) 621-5512. Walk-ins are welcome at our office, 311 Fair Lane in Placerville. For more information about our public education classes and activities, go to our Master Gardener website at ucanr.edu/sites/EDC_Master_Gardeners/. Sign up to receive our online notices and e-newsletter at ucanr.edu/mgenews/. You can also find us on Facebook.
Don’t miss the fifth annual Master Gardener spring plant sale on April 19. Featured this year will be many varieties of heirloom tomatoes along with perennials, trees, shrubs and groundcovers that do well in our foothill climate. Plants that are considered water-wise will be prominently pointed out. Check our website for the latest information on the times and location of the popular plant sale.