By Cindy Weiner, UC Master Gardener of Butte Count, November 16, 2018

One approach to dealing with drought conditions in the garden is to turn to native plants that are well-acclimated to our local environment. Some gardeners new to planting natives may be concerned that these plants might require special care, but in general they need not worry. While some natives can be difficult in the garden, most are not, and many are very easy to grow. Three local landscape designers specializing in native plants offer the following suggestions for “no fail natives.” In addition to being easy to care for, these particular plants give a threefold return on one's investment: they are attractive, versatile, and provide valuable support for wildlife in the garden.

Eve Werner, landscape architect and owner of Eve's Garden Design, likes to use coffeeberry (Frangula californica) as a screen, background or hedgerow. Its blackish berries resemble coffee beans and are very attractive to birds. This evergreen shrub can grow to six to ten feet tall and wide although the cultivar ‘Eve Case' is smaller, only reaching about five feet. It is native to Butte County and grows in Upper Bidwell Park. Werner says, “This adaptable plant thrives in full sun to shade with monthly to no summer irrigation.”

John Whittlesey, owner of Canyon Creek Nursery and Design, is a fan of Cleveland sage (Salvia clevelandii) for its “fragrant foliage, showy flowers that attract an array of pollinators, and extreme toughness for full sun and little water.” This woody perennial blooms in early summer with spikes of blue flowers in whorls around the stem. Whittlesey suggests planting them with the robust matillija poppy in larger gardens, or with the white-flowered native yarrow in smaller gardens. Cleveland sage grows three to five feet tall, although the cultivar ‘Winifred Gilman' is a little smaller.

Jason Mills, owner of Ecological Solutions, suggests, “If you're looking for an evergreen shrub, why not try giving the local and less commonly used hollyleaf redberry (Rhamnus ilicifolia) a shot?” Hollyleaf redberry has small serrated leaves, resembling holly. It grows best in full sun or partial shade. The flowers are small and inconspicuous but develop into beautiful red fruit, which provide food for birds. It grows five to ten feet tall and needs no summer water once established.

Both Werner and Whittlesey recommend California buckwheat (Eriogonum fasciculatum), one of several species of buckwheat that are native to California. Werner says, “California buckwheat is an evergreen shrub with a whimsical, mopsy form, much like baby's breath on steroids. Its pom-pom-like flowers bloom white in summer and then age from dusky pink to deep russet.” Whittlesey likes growing it in a sunny dry border with California fuchsia, penstemon, yarrow, sages, flax and grasses. It attracts many native bees when blooming. California buckwheat grows to about 3 feet tall and wide and needs no summer water once established.

Mills and Whittlesey like using the large perennial bunch grass deergrass (Muhlenbergia rigens). Whittlesey says, “I use deergrass to bring a rhythm and flow into a garden. When in flower in later summer, it has a stronger architectural form which holds through the winter months. It combines readily in front of larger shrubs or as a foil for small shrubs and perennials.” Deergrass forms a dense clump to 4 feet tall and wide in full sun or light shade.

Growing natives can be easy if you give careful consideration to the plant's cultural requirements. Mills states, “In the end it all comes down to putting the right plant in the right spot. We look to nature and try to match the conditions (substrate, moisture, light exposure) found in remaining intact habitats when we create our designs and implement native landscapes. When you get it right, you'll know, as they thrive for years to come with little to no water and maintenance and provide crucial resources for wildlife along the way.”

 

By Alicia Springer, UC Master Gardener of Butte County, November 2, 2018

When that first light rain fell over our region in early October, a collective sigh of relief fell as well. We all agree that rainwater is precious—so why do we try so hard to move it off our property? On city and suburban lots, we channel rainwater from roof gutter downspout to street gutter storm drain as directly as possible. We don't want rainwater pooling around our foundations or settling into muddy sumps in our gardens, so modern houses and driveways are engineered to clear the runoff. But why not capture that precious rainwater in the soil? “Slow it, spread it, sink it” is the rallying cry of this permaculture principle of rain capture, and with some fairly simple landscaping—small berms, swales, and basins that direct, detain, and filter water—we can invigorate our soil ecology, enhance our yard's aesthetic and habitat value, filter pollutants and help relieve over-tasked city storm drains.

Chicoans have a macro-example of this approach to storm water in our own Lindo Channel, which catches the overflow when Big Chico Creek runs high. While many towns direct excess storm water to concrete flood control culverts which whisk the water to treatment plants, Lindo Channel's runoff nourishes a riparian corridor of oaks, sycamores, willows, cottonwoods, and bay trees (along with nonnative brush). The stream flow recharges upper-level groundwater, and the greenery helps clear air pollution and offers sanctuary to birds and other animals large and small.

The goal of on-site rain capture is to allow water to percolate into the soil rather than to create holding ponds, which require more complex engineering (and can foster mosquito breeding). Any effective rain garden landscaping should discourage standing water and allow flow to infiltrate the soil within a day or two. This can be as simple as a gravel-lined trench (often called a french drain) leading from a downspout to a grassy meadow or planting bed. A more complicated retention basin might entail layers of soil, gravel, and sand designed for slow seepage. For the purposes of this brief introduction, let's focus on a versatile and relatively simple structure, the swale.

A swale is a shallow channel, bermed a bit on both sides, that lets gravity do the work of moving rainwater along a gently sloping course. The swale directs water away from structures and through a straight or meandering depression lined with river rock, grasses, or other vegetation that can tolerate periods of winter wet and summer dry (regional native plants generally fit the bill). A grassy, vegetative swale might be lined with cool-season native meadow grasses such as sedges (Carex species) or rushes (Juncus species) that thrive with winter moisture and go dormant over the dry summer. A rock-lined swale resembling a dry creek bed holds visual interest throughout the seasons. Water-loving plants can be sited closer to the flow, while more water-averse selections can keep their feet dry further up the banks.

Before planning your swale, observe your yard's topography and note where and how rainwater settles in the wet season. Are there existing declivities where the ground turns soggy? You might run a swale through that area to create better drainage, or you might construct an improved basin, but you should avoid adding water that will just sit there. Is there a natural slope you can work with? Great! Do you have areas of impacted clay that shed water like a duck's back? Cutting a gravel-lined swale through hardpan could be helpful, but difficult.

In general, your rainwater collection surface should slope downward from the water source, or you can create a minimum 2% slope. Steep slopes can create erosion, so avoid orienting your swale down slope in such areas.

Locate your swale:

• At least five feet away from structures without a basement, or ten feet from structures with a basement.
• Away from septic systems and leach fields
• Away from a tree's crown or major root zone to avoid root rot
• In full or partial sunlight to support plantings

Think of your roof as the watershed, the downspout or water chain as the headwaters, and a downpour as a flash flood. Construct your swale to withstand those rare, brief, but potentially powerful erosion-causing pressures. The channel should be at least 6 inches deep, and lined with grasses, gravel, or river rocks for the dry creek effect. Use the excavated soil to build up gently sloping berms on each side.

Anchor your artificial creek bed with larger stones, boulders, and deep-rooted plants such as deer grass (Muhenbergia rigens) and fescues (Festuca species). If space permits, larger shrubs can create a more dramatically varied look. Vegetation should be planted and at least partly established before the winter storms, so be prepared to irrigate in dry periods and through at least the first summer. Once well established, deep-rooted native plants will enjoy the cool season storm water and survive the summer heat.

The illustrations here depict a professionally-designed creek bed along the driveway of a family home in Chico near lower Bidwell Park. A DIY project could be smaller in length, width, and overall scale while still employing some of the elements that make this feature so delightful.

From a simple gravel channel to a dry creek to a more elaborate retention pond, the hardscape elements of a rain garden project may seem daunting without step-by-step instruction. “Coastal California Rain Gardens” published by University of California Agriculture and Natural Resources (UCANR), offers detailed information about planning, building, and maintaining a rain garden. Another useful guide is “Slow it, Spread it, Sink it! Rain Gardens and Swales” published by the Napa County Resource Conservation District. Both publications offer additional plant suggestions and resource listings.

Additional information and plant names used in photos:

A dry creek rain swale in a suburban garden landscape. The swale, roughly 50 feet long x 10 feet wide, runs along a sloping driveway. Redbud (Cercis occidentalis), deergrass (Muhlenbergia rigens), St. Catherine's Lace (a buckwheat, Eriogonum giganteum), Santa Barbara daisy (Erigeron karvinskianus) and California fuchsia (Epilobium canum) are among the native species seen.

Plants that tolerate winter moisture and summer drought line the banks of the swale. Idaho fescue (Festuca idahoensis) and California fuchsia (Epilobium canum) are seen. A redwood (Sequoia sempervirens) is on a raised bank so rainwater can irrigate but not saturate the root area. The redwood will require summer watering to stay healthy in the Butte County climate unless it's near a perennial stream.

A decorative rain chain at the ‘headwaters' of the creek bed directs flow from the roof gutter. Note that the creek bed is directed away from the base of the redwood, which is on a higher bank.

Boulders and deergrass (Muhlenbergia rigens) stabilize the slope and provide pleasing visual variety. Larger native plant selections screen the property. These include toyon (Heteromeles arbutifolia), mountain mahogany (Cercocarpus betuloides), deer grass, and redbud (Cercis occidentalis). 

Diagram of a grass-lined vegetative swale courtesy of Napa County Resource Conservation District.

By Jeff Oster, UC Master Gardener of Butte County, October 19, 2018

Two weeks ago in this column, we introduced a few of the most common ornamental plants in the Asteraceae family. Plants in this family are also called composites (Compositae) because they have composite flower heads made up of a central disk of tiny flowers without petals, surrounded by ray flowers that do have petals (so each “flower” head is actually composed of multiple flowers). The following are some less common composites that do well in our environment.

Echinacea is a tough perennial with brownish orange dome-shaped centers. E. purpurea (purple coneflower) can reach four or more feet in height and form a dense clump two feet wide. The four-inch flowers have purple ray flowers (petals) that droop downward. Situated in sun or part shade, these plants have a long blooming period, from June through August. They require well-drained soil and moderate to regular watering. Coneflowers require little in the way of maintenance other than dividing when they become overcrowded (about every four years). When dividing and re-planting, make sure each division has a shoot and roots. Coneflowers are self-seeders, and will multiply if happy. They attract bees, birds and butterflies; if the flowers are left on the plants, their bristly seed heads provide birds with food during the winter. Deer will eat the young plants but generally avoid mature ones. Coneflowers make good cut flowers and can be dried and preserved.

Tagetes lucida (Mexican marigold). These are carefree and easy to grow perennials, reaching three feet tall by one and one-half feet wide in full sun or partial shade. Mexican marigold needs well-drained soil and is fairly drought tolerant. The yellow flowers provide color in the late summer garden, blooming from August into September. Bloom time can be extended by deadheading. A hard freeze will kill Mexican marigold to the ground, but it will come back in spring. Propagate from stem cuttings or root divisions.

The edible flowers of Mexican marigold can be added to salads; the narrow, dark-green leaves have a strong scent and can be used as a substitute for tarragon; and the dried leaves and flower heads can be used to brew a pleasant anise-flavored tea. This plant attracts butterflies, bees, and birds to the garden, and is generally not bothered by pests.

Grindelia camporum (gumweed) is a yellow-flowering native known as Great Valley gumplant or gumweed because the flower heads and leaves are coated with a sticky residue created by the plant. It is a gangly perennial up to six feet tall, but dies back in the winter to a basal rosette of leaves. It flowers from May to late October or early November, providing color and wildlife food through the summer and autumn months. It likes full sun, and will grow in salty, alkaline, or clay soil. Gumplant is great for a dry border, or to create meadow-like drifts in an informal (wild) garden. Propagation is easiest from seed. Gumplant is a traditional Native American medicinal plant and a major bird and insect magnet. It tolerates deer.

Helianthus maximiliani is a sunflower. It is native to the central and southwestern United States, and is therefore well-suited to our dry climate. It is a persistent rhizome-forming perennial which forms clumps three-feet wide and can reach a height of up to ten feet in a garden. The yellow three-inch wide flowers appear in late summer and bloom until mid-autumn. It thrives in well-drained soil and bright sunshine.

Apply one inch of water every week during spring and summer to the base of the plant. Pinch one inch from stem tips to promote bushy growth and flower production throughout the season. Stake tall plants to keep the clump upright. Cut back after flowering. Propagate from rhizomes or seeds. The flowers of Helianthus maximiliani can be cut to bring inside; they also dry well. Young growth on these plants is attractive to slugs, but rabbits and deer steer clear. Native Americans traditionally utilized these plants for food, dye, oil, thread, and to repel mosquitoes. Butterflies and bees gather the pollen and songbirds love the abundant seeds.

PLANT SALE – Saturday, October 27, 10am to 2pm, Rain or Shine!

The UC Master Gardeners of Butte County are holding a Plant Sale on October 27 at their Demonstration Garden at Patrick Ranch (10381 Midway, Durham). All plants have been propagated by UC Master Gardeners of Butte County and selected to thrive in our climate. Check or cash only—no credit cards. For more information on the Plant Sale, including Workshops beginning that day at 9 am and a list of plants for sale, go to https://ucanr.edu/sites/bcmg/sale/

HOTLINE – Questions? Plant problems? Pest Issues? Contact the UC Master Gardeners of Butte County by phoning our Hotline (530-538-7201), or visit our web page at: http://ucanr.edu/sites/bcmg/

By Jeff Oster, UC Master Gardener of Butte County, October 5, 2018

The Asteraceae is a very large and widespread family of plants which includes many very common species of garden flowers, such as asters, daisies, zinnias, chrysanthemums and sunflowers. This plant family is also called Compositae because its members generally have composite flower heads made up of a central disk of tiny flower without petals, surrounded by ray flowers that do have petals (so each “flower” head is actually composed of multiple flowers).

Composites are mostly herbaceous, but the family also includes shrubs, vines and trees. They have worldwide distribution, but are most common in arid and semiarid regions of subtropical and lower temperate latitudes. Most like full sun and good drainage, but will tolerate a variety of soils.

Economically important composites include safflower (for oil); many edible crops such as artichoke, lettuce, cardoon, and chicory; herbs like stevia, tarragon, coneflower and chamomile; and the humble dandelion, reviled in many quarters, but considered a useful edible in others. This article series will concentrate on ornamental long-flowering perennials adapted to our climate.

Ornamental species of Asteraceae have a range of heights, plant habits, and colors to choose from. Different species of composites can be effectively integrated into the home garden, because their similarity of flower form provides harmony in a display. Try layering plants of different heights and habits, with the shortest in front, planting them in masses. Another approach is to plant in groups of three in alternating groups, or in rows of different species. Select complementary colors (for example, pairing yellow with violet, or orange with blue), or work with a palette of primary colors (blue, red, and yellow). Large plantings of different species in a single color range can be very dramatic: try cool and orange yellows together, or yellow orange with red orange, or blue violet with red violet. Plants in the following three genera are some of the most reliable composites for our area.

Coreopsis

Coreopsis is an old reliable garden favorite, with blooms in shades of yellow, orange, maroon, and red. Some varieties bloom all the way from mid-spring through fall, and make good cut flowers. Coreopsis love sun and are not finicky about soil – they will do fine in average to poor soils, but well-drained garden soils are best. They are drought-tolerant and low-maintenance. Deadhead flowers for longest bloom and divide every few years when overcrowded to re-invigorate them. They are easily propagated by division, stem cuttings, and seed. Coreopsis are deer resistant and attract birds.

C. verticillata tolerates drought and neglect, and blooms from summer through fall. C. verticillata ‘Moonbeam' has pale yellow flowers, while the flowers of ‘Zagreb' are more golden yellow. The bright yellow C. auriculata ‘Nana' is a low-growing form that spreads by underground runners to create a two-foot-wide clump in a year. Useful in front of taller plants, it too has a long blooming season if deadheaded faithfully. Another bright yellow form is C. grandiflora, a tough variety that reaches two feet in height and spreads to three feet wide and blooms throughout the summer.

Gaillardia (blanket flower)

Gaillardia is a low-growing summer bloomer with daisylike flowers in shades of red, yellow, and orange. Plants are mounding to slightly sprawling. Gaillardia requires full sun, and tolerates drought and poor soil, but needs good drainage. Unfortunately these plants tend to be short-lived. Deadheading is not necessary but helps prolong plant life. Cutting plants to 6 inches in late summer may increase their chances of surviving through the winter. They can be propagated from seed, basal cuttings, or division. Dividing them in spring or early fall every two to three years will improve their vigor.

Butterflies and native bees love to visit these flowers, and their seeds provide food for birds. Pest problems are few; deer and rabbits avoid Gaillardia. The taller cultivars of Gaillardia make nice cut flowers.

Some varieties of Gaillardia to consider: Gaillardia aristata is a robust, large-flowered perennial which flowers in shades from yellow to red; it is native to the prairies of North America, and is often included in wildflower mixes. Gaillardia x grandiflora grows tall -- up to three or even four feet and tends to flop. G. x grandiflora ‘Tokajer' is tall, perhaps reaching three feet, with pure orange flowers. Gaillardia come in a wide variety of flower color, including various shades of red and yellow, and some have orange or maroon bands on the petals.

Other useful more compact cultivars in our area include G. x grandiflora “Arizona Sun” which has stunning mahogany-red rays rimmed in golden yellow. It reaches a height of twelve inches, and blooms sooner than many other cultivars. G. x grandiflora “Mesa Peach” and “Mesa Red” grow a bit taller, to eighteen inches, with peachy-yellow and deep red petals, respectively

Aster

Finally, plants in the genus Aster are perfect plants to think about at the beginning of the fall season because they add spectacular color in the autumn. Aster plants are very durable and long lived. Plant asters in early to mid-spring (or buy them now, in pots, to add fall color to a sunny porch or deck). They should be trimmed back in early spring and again in June to maintain bushiness; deadhead occasionally for more blooms. Divide every two to four years in the spring to maintain vigor and flower quality. The plants can be used in many places: asters work well in borders, rock gardens, or wildflower gardens. As a bonus, asters attract butterflies.

Many varieties of Aster are available, Aster × frikartii 'Wonder of Staffa' has the longest blooming season. It is a repeat-blooming aster that produces lavender-blue two-inch-wide flowers from summer into fall on bushy plants. It grows to three feet tall and one to two feet wide and prefers full sun and average, well-drained, dry to medium soil. Cut plants back by half in midspring to encourage bushiness. Divide in spring to maintain vigor as required. But be advised, this is a plant for USDA zones 4-8, a bit cooler than the valley floor, so it will not live as happily here as it will in the foothills.