Tree Varieties You’ll Love

We have Joyce Kilmer to thank for her poem ‘Trees’ that starts with the famous line:
I think that I shall never see
A poem lovely as a tree.

In nature and in the garden it’s the trees that get most of the attention. Cambridge Dictionary defines the Wow Factor as a quality or feature…that makes people feel great excitement or admiration. Majestic and dramatic, no matter the size, a tree makes a garden or landscape speak that it’s here to stay.

Brahea armata – Mexican Blue Palm

Recently I had the pleasure to spend some time in a historic garden that dates back to the 1800’s. Last year this garden was featured on the Garden Conservancy Santa Cruz Open Days. The Conservancy’s mission is saving and sharing outstanding American gardens so I was thrilled to tour this garden, be introduced to several new tree varieties plus see some old favorites that might just work in your garden also.

Many of the hundreds of tall bearded iris were still blooming in the garden as well as early flowering perennials and shrubs. I didn’t see any dragonflies flitting about on this particular day but the stunning ornamental gate and mosaic created on one of the garden paths both feature dragonflies and I’m pretty sure they are regular visitors. The garden is called Odonata which is the order of carnivorous insects encompassing dragonflies and damselflies.

An unusual flowering dogwood from Mexico. Cornus florida ‘Pringle’

One of the most unusual flowering trees in Odonata was the Mexican flowering dogwood. This small ornamental tree, a cornus florida subspecies called ‘Pringle’ had the most unusual flowers. Their white bracts don’t fully open giving them a Chinese lantern look. This tree holds its foliage later than the more familiar Eastern dogwood and has reddish fall color. Glossy red fruit that forms later in the season is readily eaten by birds. This tree is showy and best used where the flowers can be appreciated.

Wedding Cake Tree or Cornus controversa ‘Variegata’

Another dogwood variety growing nearby was also new to me. Cornus controversa ‘Veriegata’ (Wedding Cake Tree) is graceful and spectacular with beautifully layered horizontal branches. Winner of the prestigious Award of Garden Merit by the Royal Horticultural Society the tree was covered with showy creamy white flowers in flattened clusters. Later the blossoms will give way to black berries in late summer that is, if the birds don’t get them first. Fall color is a lovely yellow color.

Golden Chain Tree aka Laburnum x watereri ‘Vossii’

Also in bloom, a laburnum x watereri ‘Vossii’ (Golden Chain Tree) looked spectacular with long, drooping clusters of lightly fragrant, bright yellow flowers. This handsome tree has a beautiful spreading canopy of bluish-green foliage and is a great choice as a single specimen or even in a group planting.

Honorable mention awards would have to be shared between the red form of Henry Lauder Walking Stick ‘Red Dragon’ and the white Flat Rock leptospermum. Well maybe the cryptomeria japonica ‘Dacrydioides’ (Whip Cord Japanese Cedar) or the pinus wallichiana “Zebrina’ (Striped Himalayan Pine) would also place.

Pittosporum ‘Silver Magic’

There were so many other note-worthy specimens in this garden. From showy shrubs like pittosporum ‘Silver Magic’ to large palm specimens such as Mexican Blue Palm and a giant bromeliad variety called a puya this garden is a landscape designer’s candy store. I even enjoyed the more common plants like lomandra ‘Platinum Beauty’, variegated fortnight lily, a huge heuchera ‘a la Rochette’ blooming alongside a brilliant blue native pentstemon as well as gold flowering Moonshine yarrow.

It was an afternoon to remember between rain storms.

Wisteria – Growing Tips & Maintenance

A pink Chinese wisteria covering a pergola in Bonny Doon

Wisteria season is winding down unless you have a repeat bloomer like a ‘ Cooke”s Purple’ or ‘Amethyst Falls’. I’ve heard it all: “Why doesn’t my wisteria bloom?” or “I planted a wisteria in the wrong place, how do I get rid of it?’ or “I love my wisteria but it’s taking over the porch ?” (insert garage, house, shed or other structure) Seems we either love ‘em or hate ‘em on our own property. Growing somewhere else they are always the stars of the spring garden. If any of this sounds familiar to you here are some tips on how to handle yours.

Wisteria are one of nature’s most resilient survivors. They are able to withstand and recover quickly from difficult conditions. To some they are a little too tough for their own good with a growth rate rivaling bamboo during the summer. If you dream of a wisteria-covered pergola shading your patio here are some maintenance tips that are sure to keep both gardener and vine happy.

A pink wisteria growing under a fragrant purple variety covers a gazebo.

Wisteria are so vigorous they can be pruned at any time, keeping them in bounds and clearing out unwanted or dead growth. Prune out any stems you see extending into eaves, windows or shingles. If yours has gotten away from you, you can even prune it down to the ground and start over with training although you’ll have to wait a few years for your vine to bloom again.

To their control size major pruning is done during the dormant season. Start by trimming the long tendrils that grew over the summer back to about 6 inches from the main trunk. Cutting the tendrils back in this way will initiate flower bud development, neaten the plant up, and show off the attractive trusty, gnarly character of the vines.

Whatever time you do renovation pruning remember the response of the wisteria to aggressive pruning is to literally explode with new runners. They put energy into new vegetative growth at the expense of flowering. Make sure you keep up on ongoing maintenance pruning by removing all unwanted runners right to their point of origin. Then prune back the others to 3 buds or sets of leaves. Repeated pruning of these runners is what will eventually give you spurs of wood, short laterals that in turn will provide you with flower clusters. You need to prune these runners all season long which ends up being every 3-4 weeks.

Do not fertilize your wisteria. They do not flower well if there is an over abundance of luxuriant growth. Over feeding also ends up giving them the means to become unmanageable monster. If you have trouble getting your vine to flower an application of a high phosphorus fertilizer may promote blooming.

A diligently pruned wisteria at Filoli Garden

Maintaining a wisteria requires some diligence but the reward is worth the effort. Remember this especially during winter pruning season to make summer maintenance easier. If you find that the wisteria vine has invaded a nearby bed, cut roots with a shovel below the soil line to control any that have wandered.

Which variety of wisteria should you get to cover your arbor, pergola, tree or other structure?

A Cooke’s Purple wisteria growing on a pergola in Boulder Creek.

Chinese varieties such at ‘Cooke’s Special’ have clusters of fragrant blue-purple flowers 20 inches long. This variety can re-bloom which makes it a favorite. Chinese wisteria can take up to 20 years to mature enough to produce flowers, but once it has matured, the plant is very long lived and can live up to 100 years.

Japanese wisteria like ‘Caroline’ bloom early with mauve flowers. ‘Royal Purple’. known also as ‘Black Dragon’ , has sweetly scented dark purple flowers. Japanese wisteria are most effective when grown on pergolas so their long flower cluster can hang freely.

American wisteria, native to more eastern areas of the U.S. is a smaller, less invasive species that grows ar about a third the rate of Asian wisteria. ‘Amethyst Falls’ blooms at an early age with lightly fragrant purple racemes. Use in containers for porch or patio, train up an arbor or trellis or as a small free-standing tree.

Silky varieties produce a profusion of short, 6 inch, fat clusters of strongly scented flowers that open all at once. They have velvety seed pods and bloom best in full sun.

All parts of the wisteria vine contain a toxin known as wisterin which can cause stomach upset. Growers should also be wary of pets and children eating the flowers or seed pods.

Plant Problems- What’s a Gardener to do?

Just one of many banana slugs in my garden

Everything was growing nicely in the garden until the banana slugs and squirrels started eating me out of house and home, fungal leaf spots and aphids appeared and the gophers and deer decided they really liked my plants. What’s a gardener to do?

Troubleshooting is a form of problem solving. And whether it’s your car, your smart phone, an irrigation system or yellowing leaves on a plant the goal is to find the solution and make everything work again. When you eliminate the potential causes of the problem hopefully the solution restores everything to its working order. Sometimes this is easier said than done as we all know.

A few weeks ago I received a text with pictures of some plants with leaf spots and was asked for a solution. Over the winter we received a lot of rain so I wasn’t surprised. But if this were mid-summer I’d suspect that the plant leaves were burned by the sun and not getting deep enough irrigation. At this time of year, however, black or brown spots on leaves are fungal or bacterial problems and should be treated with an organic fungicide like Serenade which is non-toxic to bees and beneficial insects, Neem, copper or sulfur spray to prevent and control spreading. Affected leaves should be discarded.

The subject of how much fertilizer and what kind came up in another troubleshooting email. The issue was whether to use an organic high phosphate fertilizer in order to encourage bud development on a notoriously short-season tree dahlia. A single spring application of rock phosphate should be sufficient. Sometimes adding too much phosphorus can actually hurt a plant, preventing the uptake of other nutrients necessary to prevent other deficiencies. A balanced fertilizer containing all three nutrients- nitrogen, phosphorus and potassium-was recommended for the remainder of the season.

Winter yellow leaves on Meyer Improved lemon

Then there are the problems in my own garden. Well, it seems I am always trying to solve something with plants, pests or critters but now it’s the lemon tree. The older leaves of this tree are yellow. The new growth looks fine so it isn’t an iron deficiency where young leaves display green veins along with a yellowish color.

It isn’t a nitrogen deficiency either where the mature leaves slowly bleach to a mottled irregular green and yellow pattern, become entirely yellow and then are shed while the discoloration spreads to the younger leaves. I fertilized in March with an all-purpose balanced fertilizer. Citrus are heavy feeders and require a steady source of nitrogen, the ideal citrus fertilizer having a ration of 3:1:1 (N:P:K)

After eliminating other mineral deficiencies or overwatering as the problem I decided that my lemon was simply dropping interior leaves which is normal after winter but I wanted to trouble shoot all potential causes to be sure citrus greening wasn’t the culprit. If it had been this deadly disease the leaves would have exhibited an asymmetrical pattern.

To quote Sherlock Holmes “Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.” I’ll try to remember that when I’m troubleshooting my next problem in the garden. Oh and by the way my banana slug relocation program is going well.

DIY Landscape DEsign Ideas

On a lovely spring day recently I spent some time in Palo Alto enjoying local gardens. It’s amazing what can be accomplished on a small lot where every foot counts. If you are looking to add some pizzazz to your garden and not spend much money, one of the gardens I visited will be right up your alley. Here are some take-a ways for your own landscaping.

Using driftwood collected from remote Santa Cruz beaches the owner of one amazing garden created a gate, several fences, flower bed borders to keep the dog out, an arbor and even a gazebo. He found used bricks and stones to build paths and also a patio but it was all the driftwood creations that caught my eye.

Take a few moments to really look at your garden. Look at the view from inside the windows and from the driveway as you enter. Then imagine all it could be with some simple changes.

A hand made driftwood arbor

The elements of garden design, like arrangement of paths, planting beds and open spaces, shape your garden. Have you ever noticed how your eye is drawn along a path through the garden? The plantings along the sides serve to frame but it’s the style of the path itself that enhances your experience in the garden.

The materials you choose for a path determine how fast or slow your walk will be. A casual path of gravel or bark chips lends itself to slow meandering around bends in the path. Flagstone pavers set in sand with spaces left between for low growing ground covers are good choices for both major access walks and smaller paths. Be sure to space the stones no further than a comfortable stride apart.

A curved line or offset sections of paving slows movement inviting you to notice the surroundings. Curves should look as if they are supposed to be there. Place a large plant, rock or sculptural feature at a turning point so that you must walk around the object. Remember a lightly curved path makes a nice entrance walk or a stroll through the garden but stick with straight lines for a path to take out the trash or get fire wood.

Used brick tapered path in a small garden

If your garden is small, a tapering path edged with curving flower beds will seem to converge on the horizon, giving the illusion of depth and distance. Plantings of grasses in the beds will create a sense of movement.

A redwood slab bench invites one to pause to enjoy the meadow.

You can separate plants and people by designing seating along the walkways. A good spot to place seating is at a fork in the path or where two types of paving meet another. Any object you can comfortably sit on is a possibility. Besides wood or ornamental iron benches, rocks, tree stumps, seat walls and planters can also double as seating.

Limit the number of elements in the garden. Rather than trying to include everything in the garden try for a unified look with the fewest number of things. Make each one count.

A short driftwood fence to protect a planting bed

Creating interest outside a window depends not only on plant choices but also simple design solutions. Keep the garden simple and restful. Editing some of the plants will make the garden lower maintenance, too. Plants that have overgrown the space need constant pruning. Move them to a better spot.

Another tip that makes an area more restful visually is to limit your plant palette. Plants that you can see through make a space seem larger. Some plants like Japanese maple, nandina and dogwood are naturally airy while other plants like camellia can be pruned for openness. Low growing, mounding ground covers help unify the garden. Plant soothing greenery for year round appeal with seasonal color from perennials and shrubs.

The great thing about making a garden is that you don’t have to do it all at once. And gardens are easy to alter as your ideas change. A garden is never done.

Garden Tour & English Tea in Scotts Valley

Path to Heaven tall bearded iris

I know where I’m gonna be on Saturday, May11th. St Phillip”s in Scotts Valley s having their 17th annual garden tour and English tea fundraiser for local charities including their own food pantry and community shelter. This year St.Phillip’s has chosen the Teen Kitchen Project as a special recipient for funds. I’ve previously visited two of the gardens on the tour and am looking forward to the others. Here are some highlights of what you can expect on tour day.

The full High Tea Luncheon includes home made scones with jam and cream, a delicious and light soup, sausage rolls and finger sandwiches plus sweet treats such as English toffee and shortbread cookies.

Doc Hencke’s entry garden

One of the gardens on the tour has been featured several times in my column. Richard Hencke’s garden – I call him Doc – in Scott’s Valley is one not to be missed. From his roots in Oklahoma and Texas he describes himself as the “Hillbilly Gardener” but with his extensive knowledge of trees, vines and just about anything that grows he is one of the most successful and enthusiastic horticulturists I know. Wear your walking shoes to truly enjoy this garden and the changes he’s made in his landscape over the past few years – before, during and after the drought.

Richard redid his pond a couple years ago. He was tired of fighting the raccoons and algae. Steeper sides will deter the raccoons and deeper water will help to prevent algae growth. He was forced to remove a curly willow that shed leaves into the pond as their natural salicylic acid was poisoning the pond.

Below the patio the golden Mexican marigold and blue Pride of Madeira should be in full bloom along with a gorgeous stand of weeping leptospermum. Among Doc’s passions is creating visual boundaries with flowering vines that grow up into the trees. Richard will be the first to admit that some are growing better than others. Sound familiar in your own garden? Even this expert propagator is sometimes stymied by Mother Nature.

I love to hear Doc Hencke’s stories as he shows me around. Stopping at a China Doll houseplant that has now grown into a tree he tells me he thinks it’s one of the tallest specimens ever. Richard’s new desert garden along the driveway is growing in nicely although he told me that the excessive rains and cold snap this year has caused come havoc. I”m not sure about the yucca he and his brother dug up in Texas that finally bloomed a couple years ago. “I’ve only waited 52 years for it”, he laughed.

Watering can collection on vintage wagon

The other garden I’ve had the pleasure to visit is the tall bearded iris farm of Jim and Irene Cummins. Also in Scotts Valley, the iris farm has been so successful that this year when the National Convention is being hosted by Region 14 their garden will be one of the host gardens on the tour.

When I asked Jim for the growing tips last year that make his iris so spectacular he told me he mostly uses lawn trimmings and tree leaves along with the native sand to break the soil down. “Iris don’t seem to care much as to soil type, they just need good drainage”, he said. He fertilizes with a balanced granular 15-15-15 fertilizer, using only an 1/8 cup or less sprinkled around each clump around Valentines Day and again in August or September. Another tip he told me was to be sure to plant the rhizomes very shallow with only the tops showing and about 12-18 inches apart. They water every 2-3 weeks although he says they can go longer between irrigations.

Among the beds of prized bearded iris there is an impressive antique farming implement collection. This historic property dates back to 1849 when an older house was built as a stagecoach stop. Everywhere you look the Cummins’ have created an interesting vignette of plants and artifacts. On the old barn there is an impressive vintage wrench collection as well as dozens of spigot handles. Antique tractor seats, watering cans, washing tubs, rusted bed frames, wagons, old kiddie cars- you name it, Jim and Irene have collected it.

All this and more can be yours when you purchase a ticket for the tour online at http://www.stphilip-sv.net or by calling their office at 831-438-4360.

Dogwoods in the garden

Eastern flowering dogwood growing in Bonny Doon

I’m so excited. The dogwoods are blooming. Earlier this month there was nary a flowering dogwood to be found but now I’m seeing them everywhere. The native dogwoods in the Sierra are slower this year as the snow hasn’t even melted in many places yet but they’ll be blooming before you know it. If every year you vow to add a dogwood to your own garden here are some tips.

Dogwood are a good tree choice for the allergy sufferer as their pollen is not wind borne. Their showy flowers, which are actually bracts, are pollinated by insects. Their pollen is large and heavy, sticking to insects rather than becoming airborne and leading to sneezing, runny noses and watery eyes.

Cornus florida ‘Cherokee Chief’

There are four main species of dogwood trees. From the Himalayas in China comes cornus capitata. Korea is home to cornus kousa. Cornus florida is native to the east coast and the west coast is home to cornus nuttallii or the Western dogwood.

We are all familiar with the Eastern dogwood that’s blooming now. With various shades of pink or white blossoms they are stunning but rain and wind can cut short the flowering season many a year and the root system is prone to disease.

Our native Western dogwood is unfortunately prone to leaf spot fungal diseases when grown out of their range. They are a little temperamental in the garden before they reach the age of 10 years but after that they tolerate seasonal flooding and flower and grow with little care in morning sun or light shade.

The kousa dogwood is a more drought tolerant, disease resistant and a tougher plant all around. Large, showy flowers open after the tree has leafed out and remain for a long time. This makes it good for hybridizing with other varieties.

The Stella series is a mix of a florida on kousa dogwood roots. Vesuvius series is a cross of our native nuttallii with a florida as is Eddie’s White Wonder. There is also a nuttullii-kousa cross called Venus that displays huge flowers and gets its disease resistance from the kousa roots. All these cultivars strive to produce a tree with superior disease resistance and huge, long lasting blooms.

Cornus capitata ‘Mountain Moon’

Deciduous dogwoods don’t like wet feet especially in the winter. That’s how they develop fungal disease. But there’s an evergreen dogwood that can handle moisture all year round. Cornus capitata Mountain Moon is a tough tree that can handle strong winds and isn’t bothered by any pests or diseases. They enjoy lots of organic matter as do all dogwoods. Huge flowers up to 6” wide can last from late spring into early summer. After flowering, the fruits begin to form and grow into red balls about the size of large strawberries. This is the reason is it also known as the Himalayan Strawberry Tree.

Dogwoods attract a variety of wildlife. All sorts of critters use this tree for food and shelter. The giant silk moth and several species of butterflies favor dogwoods as host plants. The spring flowers provide nectar to bees and other pollinating insects. Robin and sparrow are just two of the bird species than build nests on the horizontal branches and many others seek shelter in the leaves. The high calcium, high fat, fleshy red fruits are eaten by 35 species of birds including titmice, juncos and waxwings.

Many people think of dogwoods as an understory tree but this location is often too shady. Grow them in a full or partial sun location that gets afternoon shade after 4:00 PM. Add a couple of extra drip emitters or inline drip tubing to your irrigation system and they’ll be happy.

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