- Author: Christine Casey
As we move into the hottest, driest part of the summer, many of our gardens are looking a bit worn out. It's certainly easier to stay inside where it's cool and put garden tasks off until the fall.
But the bees are still out there doing their work to bring us food and create habitat for wildlife. What are the plant options for California gardens that will stand up to the heat with little water (all these plants are rated ‘low' in WUCOLS) and be loved by bees?
One great choice is our native California aster, Symphyotrichum chilense. Unlike asters native to the eastern US and Europe, which need regular water in California, this one thrives on low water. Shown here are the cultivars, 'Purple Haze' and 'Point St. George'.
'Purple Haze' is about 2 feet tall, while 'Point St. George' grows low to the ground. The former has deeper purple flowers than in typical for this species. Both need full sun to light shade and will spread (a lot!) to cover an area. Consider yourself warned when choosing an area to plant these in.
In our studies of bee plant preference at UC Davis we found our native aster to be one of the most attractive plants to California native bees. The late summer flowers are a critical source of nectar and pollen at a time when not a lot is blooming.
The flowers age from white to rust in later summer and provide fall color in the garden into winter.
Finally, for intense late summer color, nothing beats California fuchsia, Epilobium canum. There are numerous cultivars available, but my favorite is ‘Catalina', which reaches about 3 feet tall including flowers. California fuchsia will grow in sun or shade but blooms best in full sun. As with the aster, this plant spreads over time, making it a great filler in areas bounded by paths, buildings, or roads. These serve as barriers to keep it contained, while the plant can take the hot conditions often found in these spots.
Plant all three this fall for a show next summer!
“Native plants give us a sense of where we are in this great land of ours. I want Texas to look like Texas and Vermont to look like Vermont.” — Lady Bird Johnson (First Lady of the United States as the wife of President Lyndon B. Johnson, 1963 – 1969).
Plants define the landscape. In California, besieged by the twin threats of drought and wildfire, the choice to grow native versus non-native plants is attracting more attention than ever before. What exactly are the merits of native compared to non-native plants, and how do gardeners make the best choice about what to grow in a home garden?
Native plants occur naturally in the area where they originally evolved. These plants have coevolved with wildlife, fungi, and microbes, and their interdependent relationships form the foundation of our native ecosystems (Native and Naturalized Plants for the Home Garden in Northern California, p. 1).
With this stunning variety of native plants, you might expect to see them growing on every corner and offered for sale in every nursery and home improvement store, yet this is not the case. In fact, according to the California Academy of Sciences, 75% of the original native plant habitat in California has been lost (Hotspot: California on the Edge, p. 2).
Since California natives are less commonly planted compared to non-native plants, you can become more familiar with them by visiting a local native plant garden such as the Butte County Master Gardeners Demonstration Garden at Patrick Ranch in Durham, the Alice B. Hecker Native Plant Garden at Chico Creek Nature Center, and the Native Plant Pollinator Garden at Gateway Science Museum in Chico.
But how do we know for sure that a plant really evolved in the local area? Botanical studies of the world's flora have been ongoing for many years, and the historical record includes many specimens and drawings of plants that were originally brought to America by European explorers and settlers. In addition, paleobotanists have been able to compare fossil records with modern plants to accurately identify which plants are native to an area (Native and Naturalized Plants for the Home Garden in Northern California, p. 2).
Another advantage to native plants is that once they are established, they normally need little watering beyond normal rainfall. With California experiencing an historic drought, native plants can help save significant amounts of water that would otherwise be soaked up by thirstier landscape plants. In general, native plants require less maintenance than non-native garden plants: less water, little or no fertilizer, less pruning, less of your time.
In addition, California native plants attract wildlife that use these plants as their natural habitat. For example, the many pollinators that flock to native plants can improve fruit set in your home orchard and yield in your vegetable garden. A variety of native insects and birds can reduce populations of mosquitos and plant-eating bugs. By using native plants, you support native wildlife and help preserve the balance of natural ecosystems (Benefits of California Native Plants).
“California has the greatest natural botanical diversity of any state in the United States. In addition to nearly 5,000 native plant species, there are about 1,500 non-native species that have become established in the state. About 250 to 300 of these are weeds of agricultural crops, turf, or gardens. The remaining 1,200 or so are naturalized plants of wildlands or disturbed non-crop areas, some of which are important invasive plants” (UC IPM Pest Notes: Invasive Plants).
Invasive plants can “disperse, establish and spread without human assistance,” and they cause disruption of natural ecosystems. The worst invasive species are called landscape transformers because they substantially alter the “character, condition, form and nature of the invaded habitat,” consuming resources needed for native plants to survive. When invasive plants replace native plants in the wild, wildlife that feed on the native plants suffer and may become endangered. (UC IPM Pest Notes: Invasive Plants, pp. 1-2).
Home gardeners may be surprised to learn that commonly available plants such as periwinkle (vinca major), or butterfly bush(Buddleja davidii), are listed on the California Invasive Plant Council Inventory, as are sweet alyssum (Lobularia maritima), and gazania daisy (gazania linearis). Periwinkle, English ivy, Himalayan blackberry, and Chinese pistache, among others, have invaded our own beloved Bidwell Park. You may be dismayed to realize that you are growing invasive plants in your own garden! The University of California's division of Agriculture and Natural Resources has information on how to determine whether a plant in your garden is safe to keep or should be removed (UC IPM Pest Notes: Invasive Plants, p. 7). The potential for a plant to spread from your garden to surrounding natural areas is a critical consideration in deciding whether to keep an invasive plant or destroy it.
When you shop for plants, “the key element is to know which horticultural plants are invasive in your area of the state. If a plant is listed as invasive in your region, it should be avoided for landscape use, especially for locations near natural areas. It may be safe to use in other regions, but sometimes the plant is not listed as invasive in an area merely because it has not yet become a presence” (UC IPM Pest Notes: Invasive Plants, 7).
Another fine resource for Butte County gardeners interested in planting responsibly is the list of Butte County All-Star Plants developed by the Master Gardeners and based on their experience at the Demonstration Garden at Patrick Ranch. These are plants that grow well in the local area. Almost all them are drought tolerant or require only moderate watering, and some are also California natives.
Gardeners interested in planting California native plants will appreciate the CalScape website where you can enter your address and search for plants that are native to your area. The search results are categorized in useful ways including low/very low water, butterfly hosts, very easy to grow, shade/part shade, annuals, perennials, and more. The information on each plant also details how the plant provides habitat for wildlife.
Clearly, home gardeners can support the health of natural ecosystems and conserve water in California by making wise choices about landscape plants. With non-native plants, make sure a plant is not invasive (or potentially invasive) before purchasing it, and be aware of its water requirements. Ultimately, California native plants are the best and most responsible choice, especially because of the ongoing drought and their diminishing natural habitat. The one drawback of native plants, perhaps, is that they can be harder to find; fortunately, the Butte County Master Gardeners program offers twice yearly plant sales featuring native plants at reasonable prices. One native plant at a time, home gardeners can help “California look like California” again in all its marvelous biodiversity.
Works Cited and References for Further Information
Benefits of California Native Plants, California Native Plant Society
California Invasive Plant Council Inventory, California Invasive Plant Council, 2006-2021.
CalScape, California Native Plant Society
Castillo, Dava, and Elkins, Rachel, Native and Naturalized Plants for the Home Garden in Northern California, The Regents of the University of California Agriculture and Natural Resources, 2009.
DiTomaso J.D., Bell C.E., Wilen C.A. 2017, UC IPM Pest Notes: Invasive Plants, ANR Publication 74139.
Hotspot: California on the Edge, California Academy of Sciences, 2005.
PlantRight, Plant California Alliance, 2019
UC Master Gardeners of Butte County are part of the University of California Cooperative Extension (UCCE) system. To learn more about us and our upcoming events, and for help with gardening in our area, visit our website. If you have a gardening question or problem, email the Hotline at mgbutte@ucanr.edu (preferred) or call (530) 538-7201.
- Author: Christine Casey
It's the first week of spring at the Haven and our plants are starting to look their best. For those of you who cannot make it to the garden this week, here's a brief tour of what's going on. For those who can make it, I've included some of the bees to look for.
The garden is currently open, although the cities of Davis and Sacramento are now recommending shelter-in-place. If this expands to other areas or becomes mandatory, the garden will close. Check our web page for the latest information.
Now blooming at the Haven:
Ceanothus, many species. For more detail on this genus, see this previous post.
Western redbud, Cercis occidentalis. This plant provides bright pink flowers early in the year, while leafcutter bees use its foliage for nest construction throughout the summer. This California native needs full sun and little to no summer water. It grows slowly, so it's worth buying a larger size for your own garden. It may be fed on by the redhumped caterpillar; damage occurs towards the end of the season so control is not needed.
Brandegee's sage, Salvia brandegii. This is a long-blooming California native sage. As you can see from the photo, which shows one plant, it can get quite large. Flowering from late January through May, pair it with the summer blooming native Cleveland sage (Salvia clevelandii) for season-long bloom. It also needs full sun and low summer water.
Bladderpod, Isomeris arborea. This is another long-blooming California native. It is at its peak in the spring, but will produce some flowers year-round. Our single plant is about 6 feet by 6 feet. Needs full sun and little to no summer water.
Firecracker penstemon, Penstemon eatonii. This bright red California native is used more by hummingbirds than bees, and adds a jolt of color to the early spring garden. It's soon to be followed by the foothill penstemon, a bee favorite. The firecracker penstemon can take part shade and will re-bloom if given some water after the first flush of flowers. Like most of our native penstemons, it will go dormant in the heat of the summer, at which point watering should stop.
Bees to look for this week include honey bees and the blacktailed bumble bee, Bombus melanopygus. The latter seems to like the Brandegee's sage, so look for it there.
/div>- Author: Catherine Bibeau
Two years ago I went to the Walker Canyon poppy superbloom twice; once when there were lots of people, and a second time early in the morning when there were very few visitors. It was unbelievably beautiful. I felt compelled to try to grow poppies one more time.
During a visit to the Theodore Payne Foundation in Sun Valley last year (theodorepayne.org). I picked up several packs of California Golden Poppy seed and a few packs of red poppy seed. Last September I sprinkled all but one of the packs along the dry creek bed we'd put in years ago. I kept all the seed within the rocky confines of the creek.
Fast forward to this past winter. There was another superbloom in Walker Canyon. I saw that one as well, and somehow it seemed even more spectacular than the 2017 superbloom. I wished I could have a bit of that golden glory of my own to see every day. But all I had was a dry creek bed. Period.
And then – a tiny, unmistakable poppy leaf appeared from under a rock. Later in the day, it had the company of another tiny poppy leaf. I scrutinized the seeded creek bed daily, like a 49er examining his claim, hoping to find gold. During the following weeks more and more little poppy plants popped up. I was thrilled. But that's all there was. Plants. No little golden explosions of color. I thought “Well, okay. It's a start. Better than I've done before. Maybe next year.”
On March 15 at 11:29 a.m. I saw it: One lone Golden California Poppy atop a long, reedy stem. It wasn't open, but in my eyes it was the singularly most stunningly gorgeous and perfect flower that ever existed. It was every happy holiday, birthday, and special occasion all rolled up in soft petals of golden orange. I was sure it was smiling at me.
Poppies are wild flowers; they grow where they want, and regardless of how their seeds are placed, I am certain that when no one is looking, those little seeds get up and march to the very spot they think they should be. The strictures of a human plan cannot contain them; they are an expression of freedom in nature. If we are lucky, we get to witness that expression.
The golden poppies have been joined by red poppies, appearing somewhat later than the goldens. They are growing outside of the creek bed and have shown that their design sense is far superior to mine. Each of them is perfectly situated, their size and colors in a balanced palette I could never achieve.
Next September I will again seed poppies. But this time I will toss them into the breeze, rather than in a neat arrangement of where I think they ought to grow. The poppies know much better than I where they ought to be.
Cathi Bibeau is a home gardener, growing various fruits, seasonal vegetables and a few types of ornamental flowers. And now poppies.
By T. Eric Nightingale, UC Master Gardener of Napa County
Your garden soil has the ability to absorb and store atmospheric carbon. This process, called carbon sequestration, has been in effect since the early days of Earth's history.
Plants absorb carbon dioxide from the air. As they process the gas, they break it apart, depositing carbon in the soil and releasing oxygen into the air. This process has helped create a livable atmosphere for humanity.
We know that carbon dioxide emissions from vehicles and industry contribute to climate change. Now we realize that there is another culprit, one we never saw coming: farming.
Modern agricultural practices involve an enormous amount of tillage. This frequent distribution of soil releases carbon that would otherwise remain trapped. Worse, clear-cutting and development disrupt the soil without replacing plant life. Concrete-covered land can't absorb carbon, and bare earth is believed to actually slowly leech carbon back into the atmosphere.
In response, many farmers are changing their methods. Using cover crops and keeping tillage to a minimum, they are working to reduce atmospheric greenhouse gases. Farming is a necessity but approaching it conscientiously can make a difference.
Though your home garden is likely smaller than a farm, you can also help support the environment. Using the same principles, your plants and soil can help sequester carbon. Growing cover crops, then leaving them as a mulch is the most accessible method. Mulch and compost will also help improve your soil texture, reducing the need for tillage.
Of course, growing plants of any kind is good for the environment as they absorb carbon dioxide and produce oxygen. But choosing California native plants for your landscape can provide added benefits as habitat and food for wildlife. Many native plants also use less water than traditional landscape plants.
If native plants are not your style, consider the many non-native drought-tolerant plants. As drought-tolerant gardening becomes more popular, even a necessity, more nurseries are carrying these plants.
Using landscaping techniques such as berms and swales, you can create a garden that incorporates plants with a range of water needs. Siting drought-tolerant plants on a berm—a low mound of well-draining soil—is the best way to assure they do not become overwatered. Building a swale next to the berm will create a space for thirstier plants. A swale is a ditch dug into the native soil which is then filled with looser soil. Water will run off the adjacent berm and settle in the swale, providing additional hydration to the plants there.
Garden design can also help reduce your energy consumption. A leafy tree or shrub on the sunniest side of your house can reduce the need for air conditioning on hot days. Some people cover the exterior of their homes in vines for extra insulation.
Another, perhaps less obvious, way you can aid the planet is to grow your own food. The plants themselves will improve the soil and air, but there's another benefit. Unless you shop entirely at a local farm stand, some of your produce was harvested by machine and transported by truck, both of which requiring fuel that contributes to global warming.
With so many people on the planet, and so much that seems beyond our control, it is easy to think that our actions don't matter. Yet small changes can produce big results, especially when we work together. Many people using a little less water adds up to a lot of water saved, and just imagine how much healthier and more self-sufficient our community would be if everyone had a vegetable garden.
Workshop: U. C. Master Gardeners of Napa County will conduct a workshop on “How to Plan and Plant a Home Vineyard” on Saturday, January 12, from 9 a.m. to 1 p.m., in Yountville. Location provided upon registration. Join our Integrated Grape Team members to learn techniques for planning and planting a home vineyard. The workshop will be held at a new home vineyard planted last year. Learn the necessary planning steps, become familiar with the checklist of activities, methods of determining the proper rootstock, selection of wine grape varietals for specific locations and estimated yield calculations. Review our calendar timeline for planning, site preparation, initial planting and timing of the first harvest for a new home vineyard. Online registration (credit card only); Mail-in/Walk-in registration (check only or drop off cash payment).
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:/napamg.ucanr.edu) 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.