Category Archives: shrubs

Make Every Drop Count:Best Watering Practices

Low water-use leucospermum or Pincushion.

Water is our most precious resource. One of the Apollo 11 astronauts recently said that the look back from the moon at our planet and blue oceans to be even more impressive than the moon itself. Life can’t exist without water. You are the steward of your own piece of planet earth. How you water can make it thrive and you can save water at the same time.

With summer water bills arriving this is a good time to re-visit how often and how much to water that landscape you’ve spent so much money to create. Basically, you’re wasting water if you water too shallow or too often. Here are some guidelines.

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. At temperatures about 104 degrees, however, 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.

California native Fremontodendron

Plants have natural systems that respond to heat problems. 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 can take resources away from a plant’s other needs like growth, flowering and fruiting.

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

Be sure that you water trees and shrubs deeply checking soil moisture first with a trowel. Established small to medium shrubs should be watered when the top 3-6″ is dry, large shrubs and trees when the top 6-12″ is dry.

As a rule of thumb, trees and large shrubs need deep but infrequent watering. 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.

Apply water with a soaker hose, drip system emitters or hand held hose with shut off and soft spray attachment according to your water district’s 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 thin, smooth rod 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 waterings 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.

grevillea lanigera ‘Mt. Tamboritha’ groundcover

When is the best time to water? Watering in the morning is the most efficient whether you water by sprinkler, drip system, soaker hose or by hand. The water soaks deep in the soil without risk of evaporation. It bolsters the plant for the day and has dried from leaves by evening reducing the risk for foliar diseases like mildew. Plant roots are also more receptive to watering in the morning.

Is it true that water droplets will scorch leaves in the midday sun? According to a study, fuzzy-leaved plants hold water droplets above the leaf surface and act as a magnifying glass to the light beaming through them so there is a very slight chance of scorch. The study also reported that water droplets on smooth leaves, such as maples, cannot cause leaf burn, regardless of the time of day.

Shady Garden Success Stories

If you read my column regularly or even once in a while you’ve probably heard me lament about the difficult growing conditions here in my garden. Between the sandy soil, 5 hours of intense sun but for only 6 months of the year, gophers, squirrels, moles, deer and chipmunks I’m happy if any plant thrives. So it is with pleasure that I report to you the small successes I’ve had lately and maybe give you hope that you might also grow plants that provide some color and fragrance in your garden along with attracting hummingbirds, songbirds, bees and butterflies.

As the sun shifts lower in the sky, my garden becomes shadier each day. The soil is still warm, however, and that encourages root growth so even though I won’t see much happening above ground until late next spring hope springs eternal and I am driven to plant more natives as well as other appropriate plants that will fill in those blank spots.

Gaura l. ‘Siskiyou Pink’

This week a clump of deep pink gaura lindheimeri is blooming like crazy. If I had my druthers I wouldn’t have planted it among a stand of orange flowering California fuchsia but it still looks great against the gray foliage of the epilobium or zauschneria or whatever it’s called now days.

Gaura ’Siskiyou Pink attracts butterflies and hummingbirds and needs only occasional water. The books will tell you gaura requires full sun but mine is thriving without a lot of sun. Don’t be afraid to try a plant you like despite what the books tell you.

Zauschneria aka epilobium

Same goes for the light requirements of the California fuchsia. Mine is happily spreading and it gets only partial sun for part of the year. Las Pilitas nursery website, a great source of information, does say they will tolerate part-shade and commonly grow where there is extra moisture in the winter and spring, gradually drying through fall. Guess that 140 inches of rainfall I got up here in Bonny Doon last winter would fall into that category. As far as the renaming of plants California fuchsia apparently is now called epilobium canum but the name zauschneria may come back so call them whatever works for you.

One of these days I want to plant a few more native plants that will tolerate shade and attract wildlife. Toyon with it’s red berries is high on my list as is Pacific wax myrtle. I have a pink flowering currant which is doing well as well as sambucus mexicana which the hummingbirds, jays and chipmunks like and a Black Lace elderberry.

Sambucus ‘Black Lace’

Of course, all the different ceanothus do well in partial shade, grow fast and the birds and bees love them both in bloom and now that they are full of berries and seeds. My covey of quail find the berries irresistible. Apparently porcupine like them also but fortunately for my dog, Sherman, I don’t have any of those.

California native Pacific Coast Iris, Woodland Strawberry, Heuchera maxima, Western Columbine, Bleeding Heart, Mimulus and Wild Ginger all do well in my lean, shady, sandy soil. For some reason I don’t have any any coffeberry or any Oregon Grape but they are both on my wish list. Coffeeberry is one of the best all around native plants for wildlife and mahonia or Oregon Grape bloom in the winter and provide much needed nectar for hummingbirds.

Take advantage of the fall planting season to spruce up the problem spots in your shady garden. Email me at janis001@aol.com if you would like more suggestions.

Flowering Trees & Shrubs of Early Spring

Outside my window the Blireiana flowering plum is covered with dark pink, double blossoms. It’s one of my favorite early spring blooming trees with a sweet fragrance strong enough to scent the garden. We look forward to the earliest flowers of the new season knowing that winter will soon be over. Spring officially begins on March 20th.

Old fashioned shrubs like flowering quince and forsythia figure prominently in many old gardens because they are tough plants able to survive neglect and still look beautiful.

Forsythia ‘Kolgold’

The bare stems of forsythia are completely covered with deep golden-yellow flowers in late winter and early spring and become the focal point of the landscape when in full bloom. The showy stems of this easy care shrub are great for cutting. Forsythias are native to eastern Asia but a chance discovery in Germany by a grower who specialized in breeding for the cut flower industry led to the especially vivid variety ‘Kolgold’ in the 1800’s. Forsythia has long been used in Chinese medicine. The flower petals contain powerful bacteria-fighting properties which make it an important dressing.

Flowering quince

Flowering quince is another old garden staple providing early color. They are easy to care for and nearly indestructible in almost any soil that is well drained and not overly fertile. Once established quince is a very drought tolerant plant and their spiny branches make them an excellent choice for hedges, screening or as a security barrier. There are red, pink, orange and white flowering varieties. The Toyo Nishiki cultivar even has pink, white and solid red flowers all on the same branch.

Clivia miniata

What would a shade garden be without a bright orange clivia? Every year I look forward to their huge flower clusters that emerge from between dark green, strappy leaves. Even in dark shade they will bloom and brighten the winter garden although they would do fine in morning sun. If you have a north facing window you can grow them as houseplants. Clivia are hardy to several degrees below freezing but mine, under an overhang, have survived temps of 23 degrees without damage. Clivia breeders have produced gold and peach colored flowers also but I still like the standard orange ones.

A beautiful vine that blooms in winter is hardenbergia ‘Happy

Hardenbergia ‘Happy Wanderer’

Wanderer’. In the pea family, this evergreen vine looks like a small wisteria when in bloom. Pinkish-purple flowers cascade in clusters on twining stems that reach 12-16 feet long. It requires little water once established and is hardy to about 23 degrees. If you have an older, tangled plant you can rejuvenate it with hard pruning in early spring after flowering. Never prune in late summer or fall because you will cut off the wood that is going to bloom the following winter.

The last plant I couldn’t live without is Fragrant Sarcococca. The tiny white flowers of this plant are easily overlooked but you can’t miss their scent. I have one near the front door that greets me with that vanilla fragrance every time I walk in or out. The flowers are followed by a bright red fruit. Sweet Box forms a natural espalier against a wall and if you have a problem spot in deep dry shade where other plants won’t grow give this plant a try. They are easy to grow, deer resistant and trouble free.

Hydrangeas-Summer Drama for the Garden and How to Prune Them

OLYMPUS DIGITAL CAMERAThere are some plants that are so showy in the garden they are worth budgeting a little extra summer water. They really get your attention.That plant for me is the hydrangea. Want instant drama in the garden? Plant one of the many hydrangea varieties. All have flowers so large they can’t help but steal the show. Easy to grow, they are pest and disease free. Here are some of my favorites and how and when to prune them.

Back in 2001 a new variety of hydrangea macrophylla was introduced. Called Endless Summer it has the unique ability to re-bloom throughout the spring and summer on both current and older season wood resulting in a much longer blooming season. This was great news for me because as sure as the sun rises, a heat wave would descend upon my garden in May and many of my traditional mopheads and lacecaps would crisp up and the show would be over way too soon. With Endless Summer I get continuous flowering through the summer. How do I prune this variety to get the most blooms?

When you read care instructions about pruning any hydrangea and they refer to new and old wood it’s really just another name for a stem they are talking about. New stems growing this growing season will be green. Old stems that grew last year are brown.

Prune Endless Summer hydrangeas as needed to keep them symmetrical. Remove dead stems you are sure will not be leafing out this year. To revitalize a mature plant-about 5 years old- remove about a third of the oldest canes in the spring by cutting them as close as possible to the ground. If your plant looks fine, leave it alone. You can prune off spent flowers in August but I prefer to leave the flower heads on the plant for winter interest.

Classic bigleaf hydrangeas -hydrangea macrophylla- mostly bloom on last years stems or old wood. The proper time to prune them is right after blossoming in July or August. Again I like to leave the dried flower heads on for fall and winter color so I prune lightly in late summer and again now lightly to shape. I may be cutting off some potential flower buds by pruning now but those stems usually flower by early fall and I’m not wacking back the whole plant.

If your bigleaf hydrangea doesn’t bloom well any more it may be time for more drastic measures. Cut back non-blooming stems to about 6 inches high. This will stimulate the growth of news productive stems.

hydrangea_paniculata_LimelightAnother showy hydrangea with huge pyramidal flowers is called hydrangea paniculata or Pee Gee hydrangea. With chartreuse blooms, Limelight is one of my favorites. They tolerate drought better than other hydrangeas which is another plus. Because they bloom on new wood in midsummer into fall, prune them in winter or early spring. Cut away old flowers and prune to open the plant to sunlight.

Hydrangea arborescens like ‘Annabelle’ produce enormous white flowers and also bloom on new wood during the summer prune during the winter or spring. This is the variety you see grown as hedges. I think I need one of these in my garden.

Vying for attention in my garden is the oakleaf hydrangea or hydrangea hydrangea_quercifolia_bloomquercifolia. I love this plant because it is so versatile. I often include it in a landscape design because it is easy to grow in a variety of situations from deep shade to mostly sun and it tolerates some drought. The stunning summer display of elongated, creamy white flower clusters age to pink by autumn and then papery, rusty brown in winter. But it’s the fall display of handsome leaves that resemble oaks that will get your attention. Mine turns the color of bright burgundy but I’ve seen bronze and crimson color on others. Prune them in early summer right after flowering.

Even in our coldest winters, hydrangeas in our area are easy to grow and don’t suffer winter damage to the flower buds as those in snow country do. Lucky us. I’m looking forward to my hydrangea show which will last most of the year.

Will Any Plants Thrive in Dry Shade?

daphne_odora_AureomarginataLooking out the window on a rainy day I forget that spot way back in the shade in the back of the garden will be bone dry come summer. It’s too far away to water conveniently very often with a hose and extending the irrigation for just that one area under the trees in the shade is not practical. I sympathize with clients when they ask me what will grow in a problem area like this. Believe me I know it’s a challenge to bring in some colorful foliage, texture or might I be so bold as to want flowers, too? Take a tip from one who lives in a similar area with the same problems. We’re in this together.

At this time of year when the plums are blooming and the flowering pears are clothed in white blossoms, I want something to extend this look out in the garden. There are several plants that bloom early in dry shade and fortunately they are also deer resistant. Later in the season when soil moisture all but disappears there are other plants that will take over center stage.

But first here are the candidates for early spring color and fragrance in shady gardens.

Fragrant Winter daphne is a handsome evergreen shrub and I especially like the variegated foliage of the variety ‘Aureomarginata’. This small, deer tolerant shrub is good looking year round and does well under the shade of small trees. Although many daphnes are tricky to grow, this one is adaptable and easy to please. During the summer water it as infrequently as the plant will allow. This is usually about once per month. Little or no water in summer will reward you with clusters of fragrant purple flowers that start opening at this time of year. Cut them to bring inside with hellebore for a pretty bouquet.

For fragrant May flowers try daphne burkwoodii ‘Carol Mackie’ which is also easy to grow and requires only occasional water as does daphne transatlantic ‘Summer ‘Ice’. Summer Ice produces sweetly scented flowers for an extraordinarily long time. Flowering begins in early April and can continue as late as November.

Another powerfully fragrant plant for dry shade is commonly known as sweetbox. Sarcococca may not be showy enough to give to your Valentine but the sweetly scented flowers attract hummingbirds and fill the winter garden with a delicious fragrance for weeks starting in January.

Sarcococca ruscifolia forms an upright bushy shrub about 4 feet tall. Another variety called sarcococca hookeriana humilus makes a great ground cover as it rarely exceeds 1 1/2 feet tall. Both plants have dark green leaves, attractive berries and are deer resistant.

helleborus_orientalisHellebores are another winter blooming plant with foliage that looks great, too. I have several varieties including orientalis, argutifolius and foetidus. My Golden Sunrise has large, canary yellow flowers. It’s been blooming for almost a month and will continue for several more weeks. Hellebores are often still flowering during the Christian season of Lent from which they get their common name, Lenten Rose. They are good plants for naturalizing under trees as they are low maintenance, survive with little water and are disease free.OLYMPUS DIGITAL CAMERA

Other plants that bloom at this time of year and require only moderate summer irrigation include Lily-of-the-Valley shrub, clivia, bergenia, mahonia and Pacific Coast iris.

As summer approaches other plants and shrubs will lend their color and texture to the dry shade garden.

Western Wild ginger and Pacific Coast Iris are great ground covers. Good shrubs include deer resistant Osmanthus fragrans or sweet olive. Their white flowers are tiny but powerfully fragrant. Bloom is heaviest in spring and early summer but plants flower sporadically throughout the year. This compact shrub grows at a moderate rate in full sun to partial shade and reaches 10 feet.

Heavenly bamboo are work horses in the shady garden. For a different look try growing nandina filamentosa or Thread-leaf nandina. This evergreen small shrub grows to 2-3 ft tall with very lacy, almost fern-like growth. New foliage is reddish in color and during the fall the leaves turn orange or purplish red. Pinkish-white flowers bloom in clusters in late spring and summer.

There are lots of other shrubs and plants that require only occasion summer water for those shady spots. Email me and I can share even more ideas and suggestions.

Treats & Tips for the September Garden

salvia_m_Hot-LipsYou can feel the weather changing as summer winds down. It’s more than just the passing of the Labor Day holiday and the school year starting. The nights are longer and cooler. The days are not quite so hot and the flowers in the garden seem brighter and more colorful. I look past the soft blue and lavender blossoms and am drawn to the warm shades of gold, rust, orange, hot pink and red. They shout autumn is on the way.

There’s nothing quite like adding a few new perennials to brighten up the garden. There are many that don’t require a lot of water after they become established. I recently visited a garden where the irrigation was reduced to the point that that most of the plants were barely hanging on. But there among the crispy plants were two Hot Lips salvia blooming as big as you please. This plant is popular for a reason. Hummingbirds, butterflies and bees love it and it blooms for a long time. It stays compact and is a great carefree shrub for water wise gardens.

Daisy flowers always bring a smile to my face. As members of the composite family they have echinacea_Wild_Berrya flat landing surface for butterflies to land on. Coneflowers are one of my favorites. When they start blooming in the early summer I enjoy them both in the garden and as cut flowers inside. Some have a slight fragrance. Hybridizers have introduced beautiful shades of gold, yellow, orange, burgundy and coral in addition to the traditional purple and pure white. Because they are dormant in the winter they are good candidates for the garden that has summer sun but winter shade. They are not attractive to deer and are good additions to the low water garden.

gaillardiaAnother perennial that blooms throughout summer and fall is gaillardia also known as blanket flower. I’ve seen this tough plant grow in neglected gardens that the owner swears does nothing to keep it going. They are covered with dozens of large reddish-orange flowers with yellow edging and bloom over a long period. This plant also attracts butterflies. You can start perennials from seed at this time of year for next year’s bloom.

Don’t overlook the color of other foliage plants like Orange Libertia, Abelia ‘Kaleidescope’, New Zealand flax, red fountain grass and Japanese bloodgrass in the garden.

Now through October, divide summer blooming perennials like agapanthus, coreopsis, daylily and penstemon that are overgrown and not flowering well. You can also divide spring blooming perennials like candytuft, columbine, astilbe, bergenia and bleeding heart but sometimes they don’t bloom the first spring afterwards due to the energy they use re-establishing themselves.

Another thing to do while out in the garden this month is to cut back berries vines that have produced fruit. Canes of the current season should be trained in their place.

Spider mites are especially prolific during hot, dry weather. Sometimes you don’t even know how bad the infestation is until all your leaves are pale with stippling. Periodically rinse dust and dirt off leaves with water. Spray the undersides of infected leaves with organics like insecticidal soap switching to neem oil if they build up a resistance to one of the pesticides.

Soon it will be time to start cool season veggies or plant cover crops in the garden. It’s never too soon to start planning for erosion control in those areas that caused you problems during last spring’s storms. But for now add some early fall color and have fun in the garden.