Category Archives: flowering shrubs

San Francisco Flower & Garden Show 2012

Every year after attending the San Francisco Flower & Garden Show I'm exhilarated by the creativity of the display gardens  and the fresh use of familiar plants. Don't even get me started on the new plant introductions I want to use in my next landscape design. This year the world-class show celebrated its 25th anniversary.

A Flower and Garden Show is a huge and complex production. Creating the 20 display gardens is a demanding task and planning for them begins many months before the show opens. By the night before the show opens 1,200 cubic yards of sawdust and mulch ( that's about 150 dump truck loads ) have been spread and 280,000 pounds of rock stacked in undulating walls and water features.

The flowers and plants for the garden come from all up and down the West Coast. Many plants are forced into early bloom for the show as Mother Nature doesn't always cooperate. Even flowering trees are sometimes kept in greenhouses so that their buds can be timed to open the week of the show. It's not a perfect science. One display garden creator who garnered 5 awards told me that hundreds of daffodils she had planned to use in her garden bloomed a week early due to warm weather. 

This year the theme of the show was "Gardens for a Green Earth". There were tips for edible gardening at home including containers for herbs and veggies on the patio and small space gardening, too. One of my favorite gardens combined tomato and flowering vines cascading over the edge of a stone vaneer wall.  Raised vegetable boxes bordered the deck for easy access and a stone water fall splashed into a huge half oak barrel.

Another interesting garden was the Low Impact Bay Friendly Garden. Modern in design, this low water-use garden featured tall raised beds surrounding a pervious concrete stepping stone patio set in a gravel base. Pervious concrete is said to be able to take in storm water a a rapid rate of over 5 gallons per minute per square foot of surface area. That far exceeds the flow rate needed to prevent runoff in even the most severe rain events.
The rainwater is temporarily stored in the course gravel layer underneath while it is allowed to naturally percolate into the underlying soil. This could be a good solution to solve site drainage problems.

Most of the display gardens featured water in them. Some were large affairs with cascading boulders while others were small and understated. In one, a length of copper tubing delivered a shower of drops in front of an aged corrugated iron panel. Another consisted of a simple stacked flagstone ledger waterfall flowing into a flagstone pond- a DIY project?  Even used tires were used as the base for the flagstone edging around a pond although frankly, I couldn't picture this water feature in anybody's backyard. One I did like was a simple flume of water pouring into a small metal rectangle lined with Mexican black pebbles. A little feature with lots of impact.

Fire pits were prevalent, too. From ornate fireplaces to glass filled affairs to simple metal rounds filled with cobbles outdoor living is enhanced with fire and water.

I had to laugh when a man asked me at one of the gardens what I was taking a picture of.  Well, I explained, I take photos of paths and steps and how they're put together and the materials they're made of for future reference. "Oh, that's a good idea" he said, and started taking pictures, too. All in a day at the San Francisco Flower and Garden Show.

Early Spring Flowering Plants

 I look out my window and see deep pink ruffled flowers covering my Blireiana flowering plum.   It's one of my favorite early spring blooming plants and those fragrant blossoms are strong enough to scent my garden. It grows next to an Autumnalis flowering cherry that blooms nearly every month of the year. I'm not kidding. It's the energizer bunny of the flowering tree world.  We all look forward to the earliest flowers of the new season.  What else blooms in winter that you might want to have in your garden? Here are just a few suggestions.

One old fashioned shrub that figured prominently in many old gardens is forsythia. Deep golden-yellow flowers completely cover the bare stems in late winter 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.

Hellebores are another winter blooming plant that with foliage that looks great, too. My double purple one has been blooming for well over a month now. I've got my eye on a variety called Golden Sunrise. Each plant is  different with variations of large, canary yellow flowers. Some are solid yellow but most have some degree of red veining and a red picotee edge. Some have a red starburst in the center. Hellebores bloom for six weeks or more and are deer and rabbit resistant. They are often flowering during the Christian season of Lent from which they get their common name, Lenten Rose. Use them for naturalizing in woodland areas. They are a low maintenance plant, will survive with little water and are disease and pest free.

What would a shade garden be without a bright orange clivia? Every year I look forward to their huge flower clusters to emerge from the 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. Clivias 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 and they didn't cost $599 like the plants I saw offered on the internet. I thought this price might have been a misprint but on further investigation I found another site offering the yellow Gloria clivia for a mere $950. I'll stick with my orange ones.

A beautiful vine that blooms in winter is Hardenbergia 'Happy 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 flowers of this plant are easily overlooked but you can't miss their scent. If you have a problem spot in dry, deep shade give this plant a try. It's easy to grow, deer resistant and trouble free.

February To-Do’s for the Santa Cruz Mountains

Seems to me that I'm still waiting for winter to start. I look hopefully each week at the weather forecast hoping to see a storm developing. The birds in my garden are already starting to pair up, however, and call to each other. They know  a new season has begun. So, as promised, at the beginning of each month, here's your to-do list of what you should be doing in the garden.

Each year the weather is a little different requiring some tasks to be done earlier in the month when it's been a warm winter while giving you a little extra time when it's been cold. This year we've experienced very cold nights since December so plants are still mostly dormant but spring is coming. Be prepared.

Cut back woody shrubs. To stimulate lush new growth on plants like Mexican bush sage, artemisia and butterfly bush cut back to within a few inches of the ground. Don't use this approach on lavender or ceanothus – only lightly prune them after blooming. Prune frost  damaged shrubs if you can tell how far down the die back goes otherwise wait until growth starts in the spring. Prune fuchsias back by a third and remove dead, crossing branches and interior twiggy growth. Container fuchsias can be cut back to the pot rim. Revitalize overgrown or leggy hedges by cutting back plants just before the flush of new spring growth.

Cut back ornamental grasses to within 3-6" of the ground. If  you get very heavy frost in your yard wait until the end of the month. Grass-like plants like Japanese forest grass should have all the old blades pruned off, too. You can divide them, if needed, after pruning to increase the number of plants you have.

Divide perennials before new growth starts. Agapanthus, asters, coreopsis, daylilies, shasta daisy and liriope are plants that tend to become overcrowded and benefit from dividing.

Prune established perennials later in the month if you get frost that may damage new foliage. Giving your maiden hair ferns a haircut now allows the new growth to come out fresh. Prune winter damaged fronds from your other ferns.

Begin sowing seeds of cool season vegetables outdoors. If it's been raining, allow the ground to dry out for several days before working the soil. Plant seeds of beets, carrots, chard, lettuce, peas, spinach, arugula, chives kale and parley directly in the ground. Later in the month start broccoli, cabbage and cauliflower. You can also plant starts of many of these vegetables and that stir fry will be on your table even sooner. Indoors, start seeds of tomatoes, peppers and eggplant so they will be ready to transplant outdoors in 8 weeks when danger of frost is past and the soil has started to warm up.

Fertilize perennials, shrubs and trees their first dose of organic all-purpose fertilizer for the season. Wait to feed azaleas, camellias and rhododendrons until the last flower buds start to open. Roses will get a high nitrogen fertilizer to give foliage a boost and later next month, I'll feed with a high phosphorus fertilizer to encourage blooms.

Feed chelated iron to azaleas, citrus and gardenias to green up their leaves. Cool soil makes the leaves of these plants yellow this time of year.  

Apply the last application of dormant spray. Spray with horticultural oil, lime sulfur, liquid sulfur or copper dormant spray. Do not spray 36 hours before rain is predicted. Be sure to spray the ground around each tree.
 

A Private Arboretum in the Santa Cruz Mountains

Recently I had the honor to tour a remarkable garden in Scotts Valley. This horticulturalist calls himself a hillbilly gardener but he is no such thing. Some of his plants come from as far away as Oklahoma, Texas and Hawaii. What a thrill to see spring growth emerge from the new leaves of his unusual trees, flowering shrubs and perennials.

Our first stop was to admire his large collection of echium candicans or Pride of Madeira. These stately shrubs reach 5-6 ft tall and 6-10 ft wide so they make quite a show when the huge flower clusters are in full bloom. Being deer resistant and drought tolerant they are perfect for our mountain environment. The color of the spikes varied from pink to lilac, sapphire blue and purple. This gardener is resourceful. He got many of his seedlings along Hwy 17 where they had reseeded after being used as brush to stabilize the slopes after the ’89 earthquake. The bees were really happy visiting the hundreds of blossoms on the beautiful spring day that I was there.

Tucked under wild cherry trees collected in Texas, are second generation iris of dark purple and pure yellow. Originally from his grandmother’s garden in Virginia, these iris are descendants from a light blue variety and a pale yellowish-beige douglas iris.

This extraordinary gardener also has a huge wild rose from Missouri covered now with fragrant white flowers, a wild olive from Texas and a sand plum from Oklahoma.  There is a yucca about 4 ft tall that he and his brother started as cuttings when they were teenagers in Port Arthur, Texas. He is also the proud father of a couple of bald cypress complete with "knees". This tree of southern swamps and other low nutrient areas grows woody projections above the ground or water level to act as a structural support and stabilizer allowing them to resist very strong winds. Even hurricanes rarely overturn them.

A beautiful Canary Island palm, planted from a seedling in 1996 that he had nurtured in a gallon can, is now over 9 ft tall.  Akebia vines grow up oak trees, passiflora and white wisteria vines up redwoods, a yellow banksia rose rambles up into a madrone and madevillea laxa is happy growing up an oak, too. A willow-leafed hakea salicifolia, indigenous to New South Wales and Queensland, graces his entry with its tiny, white fragrant flowers.

Other trees this gardener loves include Causarina, native also to Australia, sugar pine, incense cedar, Western red cedar, deodar cedar, staghorn sumac and a maytens tree.  His mother in Pennsylvania taught him to plant his first garden at age 4 and he cherishes his Eastern white pines, pinus stroblis, and giant sequoias, three of which he grew from seed.

And I can’t forget his collection of salvias. The red flowers spike of salvia confertiflora bloom year round. The beautiful salvia mexicana will soon to be covered with rich, blue flowers. He also grows salvia chiapensis and a salvia-like plant native to Hawaii called salvia lepechinia. This deliciously scented plant will be covered soon with reddish lavender lipstick-like flowers adored by hummingbirds like all the salvias.

A new greenhouse where he has a small collection of orchids will soon house new seedlings that are sprouting in a germination station under lights. Of the many Hawaiian seeds he has collected are maile, a flowering plant that is probably the oldest and most popular material used in leis by early Hawaiians, milo- a chocolate and malt powder popular in many parts of the world, gossypium tomentosum, coral vines, hibiscus and the koa tree.

There were hundreds more cool plants I learned about and got to admire that day. I’ll be visiting this garden again and again for the next round of wonders. it’s a marvel.

 

Time to Prune Roses, Fruit trees and Flowering Shrubs

I’ll be the first to admit it’s hard to bundle yourself up to go out and work in the garden on a cold winter day. Bright sunshine sure helps but still it’s not t-shirt weather yet. It helps to think how good that fresh air will feel, not to mention that working in the garden relieves stress. And think about all that great exercise you get without getting on the boring treadmill.

Depending on your weight and how vigorous you work, one hour of gardening can burn up about 272 calories. Transplant a shrub, and the number of calories burned could jump to an incredible 340 calories per hour. Just think of that extra helping of potatoes-au-gratin you had over the holidays.

There’s plenty to do this time of year. Neaten things up by removing rotting perennials and sweep the leaves and debris off the driveway and your roof. 

It’s time to prune fruit trees and smother overwintering eggs and insects by spraying with horticultural oil. Combine your spray with lime-sulfur ( except on apricot trees ) to kill fungal disease spores like the ones that cause peach-leaf curl.  has also been shown to supress fungal diseases.You’ll want to do this again when the buds swell but before they open ( about Valentine’s Day )

Control large vines like overgrown honeysuckle, pink jasmine,  morning glory, passion vine, potato vine and trumpet creeper by radically thinning or even cutting back low to the ground if they are a big, tangled mess. Wait until after flowering to heavily prune spring-blooming vines such as wisteria.

Pruning Roses
When buds along rose canes begin to swell, prune repeat flowering roses by removing spindly or diseased shoots and dead wood. Do this before they start leafing out which wastes plant energy. Cut back the remaining stems by about a third, cutting canes at a 45-degree angle just above an outward facing bud. Don’t worry whether your pruning job is perfect. Roses are super forgiving and you can trim them up again later. You want to produce lots of roses not just a few of exhibition size. Aim for a vase-shaped  bush with an open center.

Prune old garden roses that bloom once in the spring after flowering.
Climbing roses require little pruning. Cut out extra stems if there are too many and also cut back long established canes to about the place where they are slightly thicker than a pencil. Then cut each side stem down to several inches. This will cause the cane to flower along its complete length for a beautiful spring display.

If any old leaves still cling to the plant, remove them. Rake up any debris beneath the plant and discard to eliminate overwintering fungus spores. It’s a good idea to spray both the bare plant and the surrounding soil with a combination organic horticultural oil to smother overwintering insect eggs and a dormant spray like lime-sulfur to kill fungus spores. If you usually have a problem only with black spot you can use a mixture of 1 teaspoon baking soda with a few drops of light oil in 1 quart water and spraying every 7 to 10 days.  Thoroughly coat the trunk, branches and twigs.

Other tasks to do in the garden in January:

Cut back hydrangeas if you haven’t already done so. Apply soil sulfur, aluminum sulfate or other acidifier if you want to encourage blue flowers.

Cut back summer flowering deciduous shrubs and vines.  Don’t prune spring flowering varieties like lilac, flowering cherry, plum and crabapple, rhododendrons, azaleas, camellias, weigela and spirea until after flowering or you can cut some during flowering to bring in cuttings for bouquets.
 

What Works in your Garden?

I’m vacationing next week in southern Mexico traveling east from the state of Chiapas to the Yucatan peninsula.  In addition to exploring ruins, waterfalls, cenotes and flamingo breeding grounds  I’ll be especially interested in the local plants which vary from  hardwood forests of mahogany and cedar to tropical.  I always study how people landscape around their own homes whenever I travel.  You can get some great ideas this way.  I’ll be sharing all that I discover in next week’s column. 

Around here this is a good time to pull plants that have been struggling now that we’ve had some rain to soften the soil a bit. Pay careful attention to and which aren’t. Be realistic about plants that don’t suit the conditions you have to offer. Replace them with plants that have proven themselves adaptable and well suited to your own garden. Thoughtful editing and repetition are the key to a successful garden.  Such self-sufficient plants require far less work, water, fertilizer and pruning.

Your own personal palette of good plants for your yard are the ones that look most at home planted right where they are. They do best in the soil, sun, wind and weather your garden offers and the maintenance is a snap. These plants don’t have to be the kind of dull and monotonous shrubs that you see around some freeway ramps. They might be the shade-loving native Western swordfern for year round interest.  Planted in masses these ferns aren’t water hogs and look like nature planted them.  Or how about the easy-peasy bergenia cordifolia which will be blooming soon planted as groundcover under the trees? Large, heart shaped leaves grow to 12 across and turn beautiful bronze color in the fall. Pink to rose-red flowers on red stalks appear in late winter.

Camellia sasanqua, with glossy evergeen leaves and showy flowers in fall and winter, can be grown as a shrub or espaliered against a wall. Camellias are easy to grow and an established shrub requires only a deep watering every 10 days or so in the growing season.

Elfin thyme is the perfect groundcover between cracks in pavers paths or other areas that get light foot traffic. And if you want any planting to look better, just pop in a black mondo grass and you’ll have instant sophistication.  Not all "go-to" plants are quite so glamorous, though. Modest, fuzzy little lamb’s ears are high on my list because they grow happily in sun or shade and any kind of soil. Stachys byzantina ‘Silver Carpet’ grows only 12" tall, blooms with purple flowers and spreads to make a beautiful edging or low border

The key to preserving both our backs and the earth’s resources is to choose the right plant for the right place. Keep the plants that are thriving and replace the unhappy plants with a smaller palette of plants that have proven themselves successful in your own garden. Whether these are California natives or plants from other regions that perform well, you’ll be happy you got rid of the malingerers.