Category Archives: California Native Plants

Tranquil Blue in the Garden

With the heat of summertime upon us I’m drawn to those areas in my garden that have blue, white and lavender flowers. A hot day just seems cooler there.

Washed out magenta is nature’s favorite go-to color and the shade that hybrids will revert to it if allowed to go to seed. Among gardeners, red is a favorite color. Orange and yellow come next, then pink and purple with blue and white both comparatively rare in nature last on the list.

geranium ‘Orion’

So naturally, most of us gardeners want the elusive blue flower in our gardens. Knowing that cool colors recede, place them around the edges or at the back of a garden to make your space appear wider or deeper.

True blue flowers are rare. We use words like cerulean, azure, cobalt, sapphire, turquoise, electric blue or steel blue when describing blue flowers. Hybridizers have tried for years to produce a true blue rose or blue daylily. Blue plant pigment is hard to manipulate. It occurs in the daylily as a sap-soluble pigment and is difficult to segregate. Lilacs, purples, orchids and mauves we have and working with them hybridizers may eventually get near blue, but pure blue probably never. Recently, some companies have found a way to insert some blue in the center of their daylily flowers but a totally blue daylily has never been produced.

Rose hybridizers striving for true blue have come close by

hydrangea macrophylla

crossbreeding lavender hybrid teas in order to produce offspring having optimum amount of cyanidin, the pigment that imparts purple or magenta tones and flavone, the pigment that gives light yellow tones.The results have been more of a silvery lilac or mauve. A blue rose is still in the future although labs in Australia and Japan are genetically modifying the pigments from petunias to produce a blue rose. Their results are not yet perfected and these roses are more of a lilac in color and can not survive conditions outside the lab. It is apparently very difficult to isolate the pigment cyanadin. Delphiniums have a monopoly on it.

omphaloides

The color blue is calming and tranquil. It is the color of serenity and peace and is said to slow down the metabolism and reduce the appetite. When brightened with white or combined with yellow or orange in a complementary color scheme the results of blue in the garden are breathtaking. The great English gardener Gertrude Jekyll used plants with golden leaves or clear yellow flowers to spice up blue gardens. Just remember that blues and purples are the first flowers to fade as darkness falls so be sure to have those whites and yellows to carry your garden into evening.

There are many blue perennials as handsome as they are durable that we can enjoy in our gardens today.
Some of my favorites are old fashioned hydrangeas, violas and campanula. Both are valuable in the shade garden along with omphaloides and brunnera. The blue spikes of a long blooming peach-leaf campanula just go together with the white and green variegated foliage of Jack Frost Siberian bugloss.

agapanthus africanus

In early spring we are dazzled by our native ceanothus which bloom with deep blue, sky blue or electric blue flowers. Emerald Blue phlox subulata carpets the ground in spring with clear blue flowers that top creeping stems. Penstemon Blue Springs, a California native hybrid, carries dense spikes of bright blue, bell-shaped blossoms.

Make sure your garden has a blue section to cool you on a hot day.

Plants that Hold up in the Heat

What happens to a plant when the thermometer tops 100 degrees like it did a couple weeks ago? Planning for more hot weather this summer is a requirement for a successful garden. Are there some plants that can survive tough times more easily?

Bees Bliss salvia

Photosynthesis is one of the most remarkable biochemical processes on earth and allows plants to use sunlight to make food from water and carbon dioxide. But at temperatures about 104 degrees the enzymes that carry out photosynthesis lose their shape and functionality. A garden that provides optimum light and water but gets too hot will be less vigorous. Tomatoes, for example, will drop blossoms and not set fruit if temperatures are over 90 degrees. Plants that endure hight heat can be stunted, weakened and attract pests and diseases even if water is available.

Plants do have natural systems that respond to heat problems. Some plants are better at this than others. Plants can cool themselves by pumping water out through the leaves for a kind of swamp cooler effect. They can also make “heat-shock” proteins which reduces problems from over heating. All these strategies do take resources away from a plants other needs like growth, flowering and fruiting.

It’s no surprise that many California natives are adapted to high temperatures. In my own garden I grow several plants that are doing quite well without irrigation and handled the heat wave just fine. One is Bees Bliss Sage, a low groundcover that can reach 6-8 ft wide draping over rocks and walls. It has an extended bloom time from mid-spring to early fall with whorls of lavender-blue flower spikes. Bees, butterflies and hummingbirds all find it attractive.

salvia clevelandii

Another plant that can handle high temps is salvia clevelandii. Right now it has just started its blooming cycle of electric blue-purple flowers. They will last through the summer. This salvia survives without any supplemental irrigation but if I give it an occasional deep watering and wash off the foliage every so often its much happier.

mimulus arantiacus

Who doesn’t like color in their garden? Mimulus or Sticky Monkey Flower blooms are showy and the hummingbirds love them. The Jelly Bean series has added bright pink colors in addition to white, orange, red and yellow but the traditional aurantiacus types are the most tolerant of drought.

As summer comes along the California fuchsia will provide the color in the garden. I like it that they spread by underground rhizomes and self sow. Free plants are always welcome. I have them planted on a slight slope where they tumble over a rock wall. My bees and hummingbirds find this plant irresistible.

penstemon heterophyllus

Other California native plants that can handle the heat with little water include eriogonum, manzanita, artemisia, California milkweed, ceanothus, mountain mahogany, bush poppy, bush lupine, native penstemon, monardella, mahonia nevinii , fremontodendron and holly-leafed cherry.

Other well adapted plants that are known to be more tolerant of heat include butterfly bush, germander, rosemary, smoke tree, rudbeckia, coreopsis, lantana, plumbago, gaillardia, lilac, sedums, oregano and verbena.

These plants can be the rock stars of your garden. Some natives can survive with no water after 2 years many look more attractive with a few deep waterings per summer. And don’t forget the organic soil amendments and wood chip mulch to encourage the soil microbes and keep the soil cool.

Fragrance in the Garden

A sweet fragrance permeates the air as I step out my front door. Could it be the white flowering wild ceanothus cuneatus blooming now on the hillside and smells of plum blossoms and roses? Maybe the scent is coming from the fragrant sarcococca with those tiny white flowers you can barely see but can smell a mile away. Or could it be the sweetly scented lily-of-the-valley flowers blooming on the back patio? Make fragrance a daily delight with plants that release their perfume at different times of the day and the year.

Daphne odora ‘Maejima’

The word fragrance comes from the 17th century French word fragrantia meaning sweet smell. A garden’s fragrance can be as unforgettable as its appearance. The scent of a particular flower can make you remember past times and places. Plant them along a garden path to enjoy as you stroll, in containers to scent a deck or patio or locate them beneath a window and let their aroma drift indoors.

Several easy-to-grow shrubs have fragrant flowers as an added bonus. Mexican Orange or choisya ternata blooms most of the year. Pittosporum eugenoides, tenuifolium and tobira all have tiny blossoms that also smell like oranges. The tiny flower cluster of Fragrant Olive or osmanthus have a delicate apricot fragrance.

Iris pallida ‘Variegata’ – Zebra iris

Then there are the perennials. My garden comes on a little later than most and the buds of the fragrant variegated Zebra iris are just opening. They will smell like grape Kool-aid when the sun allows the scent to develop.

Last year Chris and Rick Moran over at Brook Lomond Iris Farm gave me a couple Zebra rhizomes and they are growing quite nicely. Every year the Moran’s have a tall bearded iris show and sale over two weekends in the spring. This May 13th and 14th is the second weekend and the show takes place at their garden located at 10310 California Drive in Ben Lomond. The Iris Farm is educational, too, as the Moran’s are well-versed in organic gardening practices.

Chris told me a scented flower story about an iris called Scented Nutmeg. Seems that when the long awaited flower finally opened she bent down and smelled nothing. The blue flower was pretty anyway. Later when working out in the garden she smelled cookies baking. As none of the neighbors were home at the time she was puzzled. Sitting down the smell hit her again and she realized she was right next to the Scented Nutmeg. They just needed the sun to warm up the flower to give off the scent.

Philadelphus lewisii at Felton Covered Bridge

Other fragrant plants include California natives Philadelphus lewisii or Wild Mock Orange. Calycanthus occidentals or Spice Bush is native to our Central and Northern California mountains. Their fragrant burgundy flowers smell like red wine. Ribes viburnifolium, carpenteria californica and rosa californica are mildly scented, too.

In spring there may be nothing quite as spectacular as a wisteria vine, loaded with fragrant purple, pink, blue or white flower clusters, covering an arbor or pergola. Pink jasmine is another vigorous vine with intensely fragrant flowers as is Evergreen Clematis.

Nemesia and Dianthus

I can’t leave out the old fashion border carnation or dianthus. Their clove-scented flowers are born in profusion making them a nice addition to the mixed flower border and containers.

The list goes on and includes scented plants such as nemesia, wallflower, Japanese snowbell, hosta, coneflower, daphne, vitex, viburnum, Oriental lily, gardenia, nicotiana, phlox, rose, sweet pea, hyacinth, lilac, flowering crabapple, heliotrope, lavender, sweet alyssum, peony, moon flower, southern magnolia.

Watering Tips when Planting for the Birds & Bees

Western Tiger Swallowtail butterfly

I may not be so fond of gophers but I never tire of the birds, butterflies and bees that visit my garden. I’m always on the look out for plants that will attract even more of these exquisite creatures and it’s one of the top requests for nearly every garden that I design. Fortunately there are many plants that fit the bill and have low water requirements for our summer dry climate.

Trees that provide fruit, seeds, nectar and protein from insects attract many kinds of songbirds. Our native Big Leaf Maple is a favorite of the Evening Grosbeak who relish the seeds and early spring buds. Another bird magnet is the dogwood. Our Pacific dogwood as well as the Eastern dogwood and even the hybrid of the two, Eddie’s White Wonder, all are very valuable sources of food for many birds. Their summer berries are high in fat and important for migratory and wintering birds.

Lesser goldfinch

There are many great low water-use shrubs and perennials that attract birds. My favorite Lesser Goldfinch is partial to the seeds of yarrow, buckwheat and aster. Kevin’s mahonia is favored by Western bluebirds. Blooming now in our own neck of the woods is Mexican elderberry. Their butter yellow flowers will form purple berries rich in carbohydrates and protein and attract an incredible number of birds. And I always can find space for another variety of manzanita or ceanothus.

Mimulus ‘Jelly Bean Gold’

Both hummingbirds and butterflies are attracted to flowers that provide nectar. Among their favorites that won’t break your water budget are natives such as penstemon and salvia. galvezia, mimulus, monardella. California fuchsia and ribes are also important nectar sources for birds in your garden. Add a couple non-native, drought tolerant perennials like lavender, gaura, coreopsis, verbena, scabiosa, lantana and wallflower and you’ll provide a feast for all your winged visitors.

So how much water do different types of plants need during the heat of summer?

As a rule of thumb, trees and large shrubs need deep but infrequent waterings. They should be on a separate valve than your smaller shrubs and perennials. Water ornamental trees 1-3 times per month depending on the type and soil. Tree roots grow 12-36” deep and require 10 gallons of water per inch of trunk diameter.

Sambucus nigra berries

Apply with a soaker hose, drip system emitters or hand held hose with shut off and soft spray attachment according to your water districts restrictions. Don’t dig holes in the ground in an effort to water deeply. This dries out roots even more. Be sure to water the root zone to the indicated root depth every time you water. Watering deeper than the root zone only means you are wasting water. You can test how deep you watered by pushing a smooth rod -1/4” – 3/8” in diameter- into the ground soon after you irrigate. The soil probe should easily slide through the wet soil but become difficult to push when reaching dry soil.

The roots of smaller shrubs are 12-24” deep in the soil. Established native shrubs may need only monthly irrigation to keep them looking their best while other shrubs may need watering every 7-10 days during the heat of the summer. Perennial roots only go down 12” or so and may need watering once or twice a week depending on type.

With lots of mulch and the above watering tips you can keep all your plants happy and healthy for the birds, butterflies and bees to enjoy.

Favorite Plants of Landscape Designers

Big surprise. Many of my friends are also landscape designers. We get together to talk plants, garden design challenges and plant problems while enjoying good food along with a little wine thrown in for good measure. Recently we met in Corralitos to exchange favorite go-to plant ideas and tour the truly fabulous garden of our host. Filled with interesting foliage and texture as well as plants that flower over a long season we all came away excited to use them in our next design. Maybe some of these ideas will work in your own garden.

Fremontodendron californicum

Every interesting garden has good bones. A successful one has a focal point, garden rooms with “walls” and a “ceiling”, plants with different textures and foliage color, repetition and unity. My friend’s garden is no exception.

Rivaling for our attention from the breathtaking view of Monterey bay, a fremontodendron, in full bloom, was a real show stopper. This California native shrub requires little irrigation and provided the perfect backdrop to the entry garden.

Loropetalum / Agave ‘Blue Glow’

Other plants that brought this garden to life included a stunning Blue Glow agave paired with the burgundy foliage of loropetalum rubrum. Both have low water needs and aren’t attractive to deer.

Eggs and bacon plant

A small recirculating fountain tucked within a pocket garden provided an inviting lure for songbirds. Surrounded by the unique lotus corniculatus or eggs and bacon plant along with a tropical-looking melianthus major aka honey bush this garden room invited one to stick around for awhile.

We garden designers were impressed with the size and vigor of acacia ‘Cousin Itt’. This lovely small plant with emerald green, feathery foliage stays small in the garden and has low water needs. Not to be confused with the bully acacia tree seen around here, it’s one of the good guys. Plant in full sun to partial shade.

Euphorbia wulfennii

In deer country you can’t go wrong with euphorbia characias wulfenii ‘Bruce’s Dwarf’. It does an excellent job of seeding itself so beware. Grow it where it can self sow and not become a problem child. Very hardy in winter and water sparingly. In spring and summer the flower heads form at the branch tips covering the plant with a chartreuse color.

A French hybrid lilac called Pocahontas scented the air as we exchanged our favorite plants that pull a garden together. The winners included hardy geraniums like Biokovo and Karmina and California native heuchera maxima. Canyon Snow Pacific coast iris also got a lot of votes. Groundcover sedum ‘Angelina’ and lime thyme garnered support also.

Abelia ’Kaleidescope’ and ‘Confetti’ got the nod from several of us. Also high on the list of favorite plants, the variegated gold and green cistus was used by many because of its low, mounding habit that hugs the ground and provides a bright evergreen accent to a sunny garden.

So if you’re in the mood to add a couple of interesting plants to your garden, take a tip from what landscape designers use or grow in their own gardens.

Sneeze-less Landscaping

It was brought to my attention by a reader who suffers from pollen allergies that blooming acacias are not the cause of allergic reactions at this time of year. Acacias are largely pollinated by insects and their heavy pollen doesn’t tend to become airborne. It’s the non-showy, quiet ones you have to watch out for.

Evergreen clematis blooming below flowering pear tree.

About 25-30 popular landscape plants are responsible for the majority of plant-related allergies in California. During the height of the pollen season- from late February to June- there are often thousands of pollen grains in every cubic meter of air. One can breathe hundreds of them with every breath. Though pollen can travel many miles, the majority tend to stay in the general area of their origin.

Redwoods, oaks, alders, ashes and other wind pollinated trees like olives, birch, box elder, cypress, elm, juniper, maple, fruitless mulberry, pine, walnut, willow and privet are the major source of spring pollen. Most native plants are good in the sneeze-less landscape but if you have bad allergies or asthma it best to avoid wind-pollinated ceanothus, elderberry and coffeeberry.

You may not be able to avoid those culprits growing on other’s property but you can get the most out of your own backyard by creating a sneeze-less landscape. Replacing existing plants may be impractical but planning future plantings with these things in mind will save you a lot of headaches down the road and let you enjoy the sunshine outside in your garden.

Clematis armandii or Evergreen clematis flowers

Flower type is a good way to judge plants. The best looking flowers usually cause allergy sufferers the fewest problems. Plants with bright, showy flowers are usually pollinated by insects, rather than by the wind. These flowers produce less pollen and their pollen is larger and heavier, sticking to the insect rather than becoming airborne and lead to sneezing, a runny nose and watery eyes.

Some trees that are good for anti-allergy gardens are apple, cherry, dogwood, magnolia, pear and plum. Shrubs like azaleas, boxwood, lilac, rose-of-Sharon, hydrangea and viburnum are also not likely to cause problems. Good flower choices include alyssum, begonia, clematis, columbine, bulbs like crocus, daffodil, hyacinth. Also dahlia, daisy, geranium, hosta, impatiens, iris, lily, pansy, petunia, phlox, roses, salvia, snapdrag

Salvia ‘Bee’s Bliss’ (good)  Ceanothus ‘Heart’s Desire’ (bad)

on, sunflower, verbena and zinnia. Lawns of perennial rye grass, blue grass and tall fescue blends are usually OK as they will not flower unless allowed to grow to 12″ or higher. Bermuda grass, on the other hand, can pollinate when the lawn is very short, sometimes as quickly as a few days after mowing.

Hopefully, our rainy weather will not cause problems for allergy sufferers. Symptoms may become worse if the body reacts to the disappearance of the pollen following its initial appearance only to have to have more of it later in the spring. According to Dr. Stanley Fineman, an allergist with the Atlanta Allergy and Asthma Clinic, “You become sensitized to it, so when you’re…re-exposed, you can get an even more violent allergic reaction.”

Here’s to a sneezeless spring for you allergy sufferers.