By Denise Seghesio Levine, UC Master Gardener of Napa County
Summer is bold and bright and warm and colorful. Except when it is not. The other side of summer is soft and gray and fuzzy. Bright, bold summer days are often tempered by soft gray fog creeping over the hills and wispy fingers of silver mist drifting through the valley in the morning, cooling and soothing.
In our gardens we can have the same bold and soft summer contrast. Summer is the time when the most colorful flowers show off: golden sunflowers; circus-colored zinnias; blue, white and red petunias; purple foxglove; red and pink asters. Dahlias and roses, lobelias and nasturtium, four o'clocks and cannas can take center stage.
With so many colors, shapes and scents, we can almost overlook the usually smaller-flowered silver and gray plants. But cool silver and gray are welcome in the garden, especially in our warm summers. Plants with fuzzy silver and gray foliage are made for our Mediterranean climate.
Why, you may ask? It is the fuzz. Look closely at these plants and you will see soft, tiny hairs covering one or both sides of the leaves. These hairs reflect the sun's rays, slow water evaporation, protect the plant from wind and cool the surface of the leaves by several degrees. Thanks to their fuzz, these understated plants are protected from brutal heat and scarce water.
Some botanists suggest that the same hairs that protect from heat also insulate from extreme cold and help keep the plant warm in winter. Herbivores are deterred by these waxy or hairy coatings, making these plants deer resistant. A plus for country gardeners.
At the garden center, it's easy to spot these silvery plants. Look for dusty miller (Artemisia stelleriana) with its lacy foliage. Or lamb's-ear (Stachys byzantina), a perennial with large, soft, fuzzy leaves that children and adults love to pet. Lamb's-ear spreads into a wide gray blanket, producing tall spires of yellow or lavender flowers.
Yarrows (Achillea ageratifolia), mugwort (Artemisia) and many sages, including Salvia argentea and Salvia officinalis, make beautiful counterpoints to neighboring plants with deep green foliage. Sages range from low-growing groundcovers to towering plants with landing pads for hummingbirds and flowers; many are wonderfully fragrant. The one exception I have found is Mexican sage which grows about three feet tall and produces lovely purple flower spires. It has survived and thrived in my garden for 35 years and looks good most of the year. But it smells terrible.
Wooly thyme and others in the thyme family belong on any list of gray-, white- and silver-leaved drought-resistant, unfussy plants. About the only way you can kill these plants is with too much kindness. These are not the sort of plants that require abundant water and compost. They will do much better in spare circumstances with scant water.
If you are perusing seed catalogs, the botanic name will help you identify these plants. White, gray and silver foliage plants have a nomenclature all their own. In Gardener's Latin: A Lexicon by Bill Neal (Algonquin Books),you will find lists with botanic descriptions for the rest of us.
The phrases alb, alba or albi in a plant's genus or species name all signify white. Candicans, eri, erio and floccosus all describe leaves that are wooly. Argent, argyro and argophyllus mean silver leaved. Greicius and incana refer to gray. Hirsutis, comosis and trychopfollus indicate a hairy plant, and arachnoides means spider-like or covered with long scraggly hairs like cobwebs. See? A whole different vocabulary. Neal's lists are extensive in his useful little book, which is still available if you are so inclined.
The madrone tree (Arbutus menziesii) provides another interesting example of the reflective qualities of these plants. Its leathery leaves have furry silver undersides that are so reflective that, on country roads late at night, they can be mistaken for oncoming headlights.
Not every white plant is drought resistant. In nature, plants evolve to survive, but humans now breed plants to be beautiful as well. So be aware that hybridized plants with white foliage may not be as tough as those produced by natural selection.
Next workshop: “Rose Care” on Saturday, June 1, from 9:30 to 11:30 a.m., at the University of California Cooperative Extension, 1710 Soscol Avenue, Napa. For more details & online Registration go to http://napamg.ucanr.eduor call (707) 253-4221.
The UC Master Gardeners are volunteers who provide UC research-based information on home gardening and answer your questions. To find out more about upcoming programs or to ask a garden question, visit the Master Gardener website (http://napamg.ucanr.edu) or call (707) 253-4221 between 9 a.m. and noon on Mondays, Wednesdays or Fridays.
Suddenly it feels like winter. Well, not really, but the mornings are definitely brisk now and the days have cooled off. We've had a smidgen of rain. Plants have stopped blooming. What are the butterflies and bees to do?
Any poor bees and butterflies still in my garden will have to look elsewhere for nectar. But I want to fix this problem so that, next fall, I will still have some blooms for my pollen-loving friends.
I fear the drought is not behind us, so I have been looking at seeds for drought-tolerant native plants that continue blooming into fall. Native plants and our native bees, butterflies and other fauna evolved together and have adapted to our winter rains and dry summers. My water comes from a well, and because I can't see what is going on down there, I am very frugal with it.
Bees and butterflies like flowers with flat heads that make it easy to gather nectar. Sunflowers are a good example. My plan is to scatter their seeds in different areas of my garden after a rain and stomp them into the ground. Then, I hope, they will not blow away and the birds will not find them before they have a chance to sprout. However, I have noticed that those cute little quail that I have invited to live in my yard are eating the tops off of some tender plants, so I will have to use floating row cover to protect the seedlings.
After reading about the nectar plants that bees and butterflies favor, I have gathered seeds for tansy, wild senna, meadow rue, yarrow, bee balm, prairie blazing star and sea holly. Some of these are annuals and may reseed if I just let the seeds drop.
I also plan to increase the amount and varieties of milkweed (Asclepias)I have in the garden. Their flower heads are the shape that most small bees and all butterflies appreciate. And the different types bloom at different times during spring and summer. The native Asclepias speciosa grows tall and blooms in early summer. As its flowers fade and its leaves get tougher, the butterflies move to later-blooming varieties for nectar and egg laying. Asclepias fascicularis (narrow-leaf milkweed) blooms in late July and August. The bees love those flowers, too.
Hot Lips sage (Salvia microphylla ‘Hot Lips') is a favorite of bumblebees. I started with a single one-gallon plant when this variety first debuted and now I have four huge plants in my garden. It needs little water and blooms almost all summer. When I visited the arboretum in Dublin, Ireland, last June, I was surprised to see it growing there. I have other salvias, too, but they do not bloom as long as ‘Hot Lips'.
Others have told me that Asclepias curvassiva, a tropical milkweed, has naturalized in some Napa Valley gardens. It has also played host to many Monarch butterflies. The plants die down in winter and renew in the spring from self-seeding. Most bees and butterflies like its nectar. Another popular milkweed isAsclepias fruticosa, sometimes called swan milkweed because of the shape of the seed pods.
Free Tree Walk: Join U. C. Master Gardeners of Napa County on Saturday, October 22, from 9 a.m. to 11 a.m., for a guided tree walk through the lovely Alameda of Trees at the Yountville Veterans Home. Established in 1884, the Veterans Home has a unique and diverse tree collection. These majestic mature specimen trees are a focal point in the lives of the men and women who live there. Come learn more about these wonderful trees. Meet at the parking lot of the Napa Valley Museum on the Veterans Home grounds, 260 California Drive, Yountville.
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.