In Praise of Japanese Maples

Trees add to the garden landscape in various ways. Often, very large trees will dominate the scene, and bring stability and grandeur to the scene, and shade a large area. In time, they can be desirable components to the garden and add value to the property.

By contrast, small trees contribute to the landscape in different ways, notably as specimen plants that attract the eye with their specific features, e.g., blossoms.

Unless you have a relatively large garden, a large trees can be overwhelming, and a small tree can be a delight.

There are many choices of small trees, which might be called “patio trees,” even though they have roles to play in all parts of the landscape.

Today, let’s review the Japanese Maple, which many gardeners and landscapers regard as the most popular of the small trees.

The true Japanese Maple is Acer palmatum. Other Acer species, including A. japonicum and A. shirasawanum, are also called Japanese Maples, and have attractive characteristics. Still. A. palmatum has been the focus of hybridizers in Japan for centuries, and has been favored by western horticulturists since its introduction to England in 1920. The species now includes well over1,000 cultivars.

The extraordinary range of sizes, forms, leaf shapes and colors of A. palmatum reflect the long history of its development and stimulate the interest of gardeners and landscapers. Those who have the pleasure of gardening in large spaces can be tempted to collect large numbers of A. palmatum cultivars.

For most gardeners, however, even one Japanese Maple can be rewarding. Even very small gardens, including balcony gardens, can be enhanced with one of these trees, which range in mature height from the dwarf varieties (three-to-six feet) up to twenty-five feet. They grow well in containers, and will ”self-stunt” when their roots are confined. This characteristic makes Japanese Maples popular with bonsai artists.

acer-palmatum-unknown-cultivarThe accompanying picture shows one of my Japanese Maples as it begins to show its fall color, which is the typical seasonal variation of these trees. It has grown to about eight feet, with distinctive red twigs, but sadly I have lost track of the cultivar name.

Many gardeners will locate a Japanese Maple as a garden feature or focal point, where the color or leaf form of the selected variety can be appreciated. With this in mind, once you have become interested in adding a Japanese Maple to your landscapes, consider where it would be best located. This decision should involve envisioning the tree in several spots in the garden, and from different perspectives. This process draws upon the most creative work of gardening. Think of your new tree as a living sculpture.

Also, keep in mind that Japanese Maples prefer part sun or indirect light, good drainage and consistent watering. They like a slightly acidic soil and do not like cold winds or salt air. Plan to provide regular watering during the first year after planting.

A Japanese Maple or several of these small trees could enhance your landscape during future years. Right now is a good time to decide on the best location, explore the range of cultivars and choose a fine selection to install in your garden before the start of winter rains. Continue reading

Restoring Soil

Several people commented on last week’s column on the carbon cycle. All endorsed the concept of restoring garden soil, to support its natural ability to sequester carbon.

One reader had questions about how to go about restoring garden soil. This is a Big Topic and you, good reader, might have your own questions, but you also might share his interests. My brief responses are below. Visit gardening.com for more details, including plant suggestions.

Q. Plow the grass under?

A. Losing the thirsty lawn is a good first step, because such monocultures are not appealing to wildlife. Plowing, however, could both promote re-growth of the grass and bring dormant weed seeds to the surface. A better approach is to kill the grass over several sunny weeks by covering it with clear plastic (solarization), or with newspaper or cardboard (smothering).

For information on Soil Solarization for Gardens & Landscapes, visit the University of California’s Integrated Pest Management webpage on the topic. The presentation emphasizes pest control; in this context, unwanted turf grass amounts to a pest.

The California Native Plant Society has Detailed lawn removal advice.

Q. Plant different grass?

A. Yes! California native grasses can provide the basis of an attractive meadow, which is more casual than a manicured carpet of turf grass. A meadow has unique aesthetic appeal; supports a variety of wildflowers and wildlife; requires little water, infrequent mowing, and no chemicals; and helps to restore the soil.

Kids on Native Grass Lawn
JACQUELINE RAMSEYER —
BAY AREA NEWS GROUP

Lily Baker’s front yard in San Jose
features a native grass lawn.
California native grasses help restore the soil.

For information on several California native grasses, visit the Tree of Life Nursery’s web page, “Masses of Grasses.”

A very good book by Carol Bornstein, David Fross, and Bart O’Brien is Reimagining the California Lawn: Water-conserving Plants, Practices, and Designs (2011).

Q. Grow more trees?

A. Absolutely! Trees and large shrubs are attractive additions to the landscape, valuable participants in the carbon cycle, and welcomed by all forms of wildlife. Invest a little research to select trees will thrive in your climate, and grow to an appropriate size for your landscape. Again, California natives are good choices.

A good introduction to California native trees and larger shrubs is available from the non-profit Nipomo Native Garden, which has produced a web page, “Native Trees for Landscaping and Wildlife.”

Q. Eliminate ground cover in favor of something with deeper roots?

A. Ground covers are any plants that hug surface or rise to any height up to four feet. Most importantly, they protect soil and soil microbiota from baking in the sun, or eroding. During the fall and winter, plant seasonal cover crops that draw nitrogen from the air and store it in their roots. Examples of such “nitrogen-fixing” plants include peas, beans, and clover. In the spring, before your cover crop sets seed, till the plants under to decompose and release their nitrogen into the soil to support the growth of other plants.

Deeper roots mean better drought-tolerance: deep-rooted plant can find moisture far below the surface. Such plants are generally preferable in the landscape, all other factors being equal.

The depth of roots varies among plants, reflecting adaptation to the plant’s environment. Among weedy grasses, for example, Annual Bluegrass (Poa annua) has roots only about right inches deep, while Bermudagrass (Cynodon dactylon) can grow to 60 inches deep in search of water.

Infrequent, deep irrigation encourages all plants to develop deep roots and drought tolerance. A common error with automatic irrigation systems is to schedule frequent, brief periods of watering. This practice encourages shallow roots, ultimately increases overall water usage and leaves plants vulnerable to dry periods.

Q. Shallower roots?

A. The advantage of shallower roots is that plants growing in arid climates have immediate access to occasional rains. Succulent plants have adapted to such conditions by developing shallow roots and the ability to store scarce moisture in their leaves, stems or roots. For this reason, gardeners often appreciate succulent plants for both drought tolerance and landscape appeal.

The New California Garden, which we envision here, features meadow grasses and succulent plants: a good time to start is now.

Tree Pruning Season

Today, we are about one-third of the way through winter, and well into dormant period, which is the right time for winter pruning of trees.

Gardeners need always to be conscious of the change of seasons, because it affects the growth cycles of our plants. Let’s review.

Winter begins on the shortest day of the year, called the winter solstice. In 2014, that day was December 21st.

The days gradually grow longer until day and night lengths are equal, marking the first day of spring. That phenomenon, called the Vernal Equinox, will occur next in about ninety days, on March 15.

The cycle then continues for ninety days. The days grow longer and the nights grow shorter until we have the longest day of the year, the Summer Solstice, which marks the beginning of summer.

Ninety days later, the day and night lengths again become equal and we will have the Autumnal Equinox, marking the first day of fall.

It is comforting in this troubled world that something of importance occurs on a predictable schedule.

So, this is the time for gardeners for winter pruning of trees.

Atlas Cedar After Storm

Atlas Cedar After a Wind Storm

Tree pruning involve practices that may be unfamiliar to some gardeners, and encourage them to avoid the work. The reality is that pruning is really not difficult, but complicated enough to that books have been written on the subject The complexities arise when considering the growth patterns of different trees, and the stylistic preferences of pruning specialists.

Without getting into all the in and outs and ups and downs of tree pruning, consider the basics. First, winter pruning, which is done during dormancy, stimulates growth in the desired directions. Summer pruning, by contrast, which is done after spring growth is done, directs or slows growth.

A third category, corrective pruning, could be done at any time, and should be done before seasonal pruning. The Four D’s of Pruning guide the removal of the following branches:

Dead – If a branch looks dead, scratch the bark to look for a green layer. If it’s green, it’s still living. It it’s not green, remove it.

Diseased –A sick branch can have various symptoms, depending the disease or insect infestation. Between cuts, clean clippers with 10% bleach water.

Damaged – Remove branches wounded or broken by storms or any other cause. They are unattractive and can foster diseases and insects.

Deranged (the root meaning is “moved from orderly rows”) – Remove suckers, water sprouts, and branches which cross or rub other branches, or point in the wrong direction.

A busy gardener might be tempted to skip this seasonal maintenance task, but trees, like everything else in the garden, grow better and look better when they are cared for regularly. Skipping seasonal pruning simply postpones the task, but doesn’t eliminate the need. Meanwhile, the tree doesn’t look its best.

Reach for your clippers!

Bare Root Trees and Shrubs

One of the best bargains in gardening is planting bare root trees and shrubs. And now is the time to do just that.

Bare root trees are dormant, by definition, and not attractive in the usual way, but they are excellent candidates for addition to your garden.

Bare Root Tree

Click to Enlarge

I have often written of the advantages of buying mail order plants, to draw from a wider selection than local garden centers can offer. That’s still a good practice for many plants, although there are drawbacks, as well: mail order buyers need to confirm that the plant of interest is right for their garden, particularly in terms of winter temperatures. Some tropical plants will not survive even the moderate winters of the Monterey Bay area, and some require more winter chill than they will receive in our climate, and will not blossom or fruit well here.

Years ago, eager to start a small orchard of antique varieties of apple and pear trees, I ordered ten bare root plants from a mid-west nursery, only to watch them struggle and eventually fail for lack of winter chill. Purely by chance, one tree, a Cox’s Orange Pippin, managed to survive my garden’s USDA zone and is producing very tasty apples to this year. That tree stands to remind me to do my homework before ordering mail order plants.

The hazards of selection are less important during bare root season because local garden centers are able to stock very good inventories of bare root trees and shrubs that are right for the local climate.

Despite the best efforts of garden centers, the economics of stocking containerized plants limit inventories of plants in pots: they cost more to ship and require more space, and offered at twice the price of the same plant in bare root.

Conversely, mail order suppliers (which still might offer a greater range of choices) can ship wholesale orders of bare root plants efficiently to garden centers, but have to recover the greater costs of shipping small quantities of plants to retail purchasers. So, for individual gardeners, the mail order price could be higher than the garden center price.

Additional benefits of buying bare root plants include larger root mass, according to researchers, easier to move and plant without soil and container, and faster growth because they adapt easily to local soil as they come out of dormancy.

The range of options at a garden center could include ornamentals, fruit trees, roses and berries. Many other shrubs could be offered in bare root form, as well, with the same advantages, but I have seen little development of that market.

When selecting an ornamental or fruit tree, look for a straight trunk, evenly spaced branches (if any), good spread of healthy-looking roots that have been kept moist, and a complete lack of any wounds or disease.

Many garden centers also offer espaliered fruit trees that have been developed by grafting branches in the right places, rather than by the time- and labor-consuming process of training. Some espaliered dwarf apple trees include grafts of several apple varieties, to produce a healthy young tree that will both fit a tight space in the garden and produce a selection of applies that ripen at different times during the season.

It is important to plant bare root specimens before bud break, so there is a small window of opportunity for the lowest prices. Don’t delay!

Flat Fruit Trees

One of the oldest advanced techniques of gardening—and one of my favorites—is espaliering, which involves shaping woody plants into two-dimensional shapes. Now, in bare root season, it’s timely to consider this tree training technique.

Espaliering has been traced back to the walled gardens of Persia, as long ago as 4,000 B.C. It was practiced during the Roman Empire and developed further during the Middle Ages.

There are good reasons for training trees or shrubs into relatively flat shapes. The primary reason in many situations is to garden productively within a limited space. Adding one fruit tree might be possible in a smaller garden, but even trees growing on dwarf rootstock can require a ten by ten area, plus some walking-around space, for cultivation. A gardener could use this tree training technique to grow several different trees in the same 1oo square feet.

Espaliers - Les Quatre Vents

These espaliered apple trees were growing at Les Quatre Vents, a notable private garden near Quebec, Canada. I took this photo in August, 2013

Espaliering is especially useful in narrow spaces along a driveway or sidewalk, or between the house and the property boundary. With an appropriate training plan, the gardener can maintain a row of fruit trees at a height of three or four feet, in a low profile that is both accessible and attractive.

Espaliered Apple Tree

Reader Bob Lippe of Seaside photographed this apple tree near a chateau in the Loire Valley, in France. The tree was being maintained at a height of only two feet.

If you have a space for which you might like to grow an espalier, check first to determine whether sun exposure is sufficient for the plant(s) you would like to install in the space. The most popular plants for espaliers are fruit trees, particularly apples, apricots, cherries and pears. In addition to fruit trees, other plants also can be grown in flat panels, including berries and climbing plants.

All the popular fruit trees—and most fruiting or flowering bushes or vines—require six or more hours of direct sunlight each day. Specific fruit tree varieties will perform better than others in the Monterey Bay area, so it would be prudent to do a bit of research before buying a tree for this purpose, or any other garden use.

Local garden centers usually offer only varieties that are appropriate for the immediate area. One could also seek the advice o the local chapter of the California Rare Fruit Growers < http://www.crfg.org/>.

In addition to making good use of limited space, espaliering has at least two additional benefits. One is to increase a fruit tree’s productivity. Training a tree to a two-dimensional form emphasizes horizontal branching, which maximizes the development of fruiting spurs. In addition, the flat form exposes more of the branches to sunlight and air, which promotes fruiting.

The second additional benefit is the opportunity for creative expression. Over the years, gardeners have developed many patterns for shaping the branches of trees and shrubs: fans, candelabras, and multi-tiered shapes are simplest to manage and most popular.

A special form of espalier, the cordon, is a single-trunked tree that develops spur clusters along its length. In this approach, branching is avoided and the trunk is trained to forty=-five degrees to the horizontal. A variation, the step-over design, brings the trunk to the horizontal, forming a low border.

For advice on growing fruit trees, attend a fruit tree workshop, such as those offered by the Friends of the UC Santa Cruz Farm & Garden: call (831) 459-3240, email casfs@ucsc.edu, or visit the Brown Paper Tickets website at http://tinyurl.com/workshops2015.

For specific information on espaliering, visit a bookstore, public library or Amazon.com for Allen Gilbert’s “Espalier: Beautiful Productive Garden Walls and Fences” (Hyland House, 2009). Any of several other more general books on pruning also would be helpful.

Visit your local garden center now for an early selection of bare root fruit trees.

Tour Offers Insights to Growing Citrus


The Monterey Bay chapter of the California Rare Fruit Growers recently organized a members-only tour of a local citrus nursery’s growing grounds, in Watsonville.

Aaron Dillon, our tour guide, shared the history of Four Winds Growers, which was started by his great grandparents. He described the current operations and the pests and diseases that are challenging the entire citrus business.

10-17-14 Aaron Dillon

One threat to citrus trees is the citrus leafminer (Phyllocnistis citrella), a very small Asian moth that lays its eggs in the tissue of citrus leaves. The eggs hatch into larva that feeds on the leaf, leaving a clearly visible, serpentine trail just below the surface of the leaf. Leafminers disfigure the leaves but rarely cause serious damage.

A greater threat is the Huanglongbing disease (HLB), which is known by the common names “citrus greening disease” and “yellow shoot disease.” HLB kills citrus trees.

A tiny insect, the Asian citrus psyllid, transfers this disease from tree to tree as it feeds. Because there is no cure for HLB, the control strategy is to find and stop the insect from spreading the disease. This pest has greatly reduced southern California’s citrus nursery industry, and has very recently been spotted in the San Jose area.

The citrus industry has developed regulations and procedures for propagating citrus trees in greenhouses, while keeping Asian citrus psyllids outside. The tour group entered an enormous greenhouse through an antechamber, in which a large fan produced positive air pressure to exclude any psyllids. The outer door closed, the fan was turned off, and an inner door opened to allow the group to enter the working area of the greenhouse.

Inside, a greenhouse worker, Alicia, expertly demonstrated the process of grafting a citrus scion to a robust rootstock. A skilled worker can graft 1,000 plants in a single day.

10-17-14 Grafting Orange Scions

Aaron Dillon engaged the interested visitors with a wide-ranging presentation of many aspects of growing citrus trees. He demonstrated the extensive facilities in a large greenhouse where roses had been grown previously, and proudly showed an even larger new greenhouse now being readied for an expansion of propagation activities.

10-17-14 Visitors in the Mist

Four Winds Growers propagates popular varieties of orange, mandarin, lemon, lime, grapefruit, and kumquat. For details, visit the nursery’s website <wwwlfourwindsgrowers.com> and click on “Our Citrus Trees.” Dillon listed three interesting varieties that consumers will enjoy in the future:

  • Vaniglia Sanguigno (acidless sweet orange)
  • Lee x Nova Mandarin (88-2 mandarin hybrid)
  • New Zealand Lemonade (sweet lemon hybrid)

For information on these and many other varieties, browse to the amazing Citrus Variety Collection website, maintained by the University of California, Riverside <http://www.citrusvariety.ucr.edu/>.

Many varieties of citrus trees grow well in the Monterey Bay area, and local nurseries have many choices in stock currently. Growing information is readily available on the websites of the California Rare Fruit Growers < www.crfg.org/> and Four Winds Growers. Pest control advice for home gardeners is offered by the Citrus Pest & Disease Prevention Program www.californiacitrusthreat.org/.

Are Your Plants Dying?

Of course they are!

All living plants age and eventually die. The only exceptions are plants that are man-made from plastic or other materials.

The aging process, called senescence, begins after the plant achieves reproductive maturity and ends when the plants dies.

Senescence is an inevitable component of plant cultivation, so gardeners should recognize and understand the process, and appreciate its benefits.

There are several kinds of senescence.

Whole Plant Senescence occurs when the entire plant dies after seed production. This occurs with annual and biennial plants, and also with monocarpic plants, e.g., the Century Plant (Agave Americana), which can grow for several years before producing seeds. The benefits of this kind of senescence include genetic diversity (each seed cycle combines genes from different plants) and increased survivability (the plant uses it resources for producing seeds, rather overwintering).

Sequential Senescence is typical of perennial plants, in which the leaves age and die, but the main shoots continue to produce new buds and leaves. This is characteristic of woody perennials, i.e., shrubs and trees, which build their roots and aboveground structure year after year, and thus increase their abilities to produce seeds and compete with other plants. A good example is the apple tree, and many other fruit-bearing trees. The tradeoff is less genetic diversity for the tree itself, although achieve genetic diversity through its fruits. Still, the tree is more vulnerable to rapid environmental changes and attacks of insects or diseases.

Shoot Senescence occurs with certain plants that die to the ground after flowering and fruiting, but retain their belowground stems and roots, which produce new shoots in the following season. Examples of such plants include the banana and the gladiola, as well as virtually all other bulbous plants.

Synchronous Senescence is controlled by environmental factors. In this process, temperate deciduous trees drop their leaves in response to seasonal changes in the temperature, typically as in late autumn. At this period, the leaves’ green chlorophyll decomposes, revealing the leaves’ carotenes, which may be yellow, orange or orange-red. In California, we look for fall color in elms, many Japanese maples, Chinese Pistach, Liquidamber, Bradford pear, flowing dogwood and others. The living fossil Maidenhair Tree (Ginkgo biloba) is noteworthy because in the fall its leaves change from green to saffron yellow, and then all fall not quite simultaneously, but within a short period.

Fall Leaf Senescence

Click to Enlarge

Woody plants also will self-prune during the growing season: leafy shoots that are not growing well die off, and the plant re-directs its nutrients to other shoots. I see this impressive self-regulatory function mostly with interior shoots that may lack sufficient exposure to sunlight. Similar, but less visible self-pruning also occurs with roots.

Gardeners need to be alert to dieback that can occur in addition to the natural processes of senescence. Such diebacks could result from controllable environmental impacts, from temperature, wind or sun exposure, insects, diseases, or herbivores; water shortages; or nutritional deficiencies. The first step in correcting a problem is analyzing its cause.

Garden Plants on the Move (Moving Trees & Shrubs)

Autumn in the garden is a good time to prepare for relocating shrubs or trees that would look or grow better in a different location.

If the thought of moving a shrub or tree troubles you, recognize that even good plants need not be permanent. Here are some reasons for moving a healthy shrub or tree.

  • The tree or shrub has grown so large it’s crowding a walkway or other plants.
  • Other nearby plants have grown so large that they are shading a plant that needs sun.
  • Other nearby plants are now gone, exposing a plant that needs shade.
  • The tree or shrub is needed elsewhere in the landscape.
  • The gardener wishes to install a new feature, and the tree or shrub is in the way.
  • The gardener has wishes to establish a thematic plant bed where an off-theme tree or shrub is growing.

When preparing to relocate a plant, first decide on where it will go. Examine the new location to ensure that it is the right place for this particular plant. Confirm that the soil is suitable, the drainage is good, and the exposure it right for the plant. Finally, make certain that the new spot could accommodate the plant when it is fully grown. Then, dig a hole twice the width of the intended root ball.

Ideally, prune the roots to protect against transplant shock. This involves digging a trench around the plant, outside the intended root ball, refilling the trench and watering to settle the soil. Root-prune in March for plants to be moved in October, and in October for plants to be moved in March.

Then, plan how to move the plant, taking its size into consideration.

Small Shrubs and Trees

For a shrub less than three feet tall, or a tree with a trunk is less than one inch wide, you could move it bareroot, i.e., without digging up a root ball. To move such a smaller plant bareroot, dig a trench around it, cutting the longer roots, wash the soil off the lateral roots, and use a flat shovel to remove the soil under the plant. Keep the roots moist until you are ready to transplant.

Not-so-small Shrubs and Trees

If you are preparing to move a plant that is between three and five feet high, decide how large a root ball to provide. For industry standards for transplanting different plants of various sizes, visit the website, americanhort.org and search for “root ball.” For example, moving a five-foot tree or shrub requires an eighteen-inch wide root ball. A root ball of that size could weigh 250 pounds, so plan for the appropriate equipment and helpers.

Larger Shrubs and Trees

Most gardeners will hire a tree service to move a tree or shrub that is larger than five feet high. If you prefer to do such work yourself, I will say “best wishes,” and predict that you will have professionals do your next transplant.

Really Large Trees

Even very large trees—up to forty-five feet high—can be moved successfully, if not cheaply. The widely available tree spade uses an array of large shovels to dig a conical divot to pluck a plant from the ground, and deposit it in a matching hole. For video clips of tree spades in various sizes, browse to YouTube.com and search for “tree spade.” To see an interesting DIY device, search YouTube for “Tree Toad 24 inch Tree Transplanter.”

Tree Spade

A mechanized tree spade makes transplanting large bushes and small or medium trees a much easier proposition. Photo: Dutchman Industries

 

A newer technology for moving larger plants is the “air tool,” which uses compressed air to blow soil away from a tree’s roots. This bareroot method avoids pruning or breaking the roots, so the plant experiences little trauma and quickly resumes its usual growth cycle. To see a brief video demo of the air tool, visit growingwisdom.com, click on “Trees & Shrubs” and scroll to the link, “How to Move Large Trees Using an Air Tool.”

After moving a tree or shrub, transplanting herbaceous perennials is easy!

Renovating the Garden —Good and Bad Views

Renovating the Garden – Good and Bad Views

Tom Karwin

In recent columns on garden renovation, we have focused on planning, removing unwanted plants and hardscape, and analyzing the garden’s soil. This column takes a closer look at objectives for the landscape.

Earlier, we wrote, “Envision how you will use the landscape: outdoors living, with parties, barbeques, etc.; recreation for children or adults; growing fruits and vegetables; or simply enjoying horticultural displays. Write it down.”

The intended uses are basic in landscape planning, but more specific objectives might be relevant to a given property. Here are two examples.

Block an Undesired View

Many homes are close to other homes, public buildings or commercial establishments, and garden renovators might wish to block the view of adjacent structures or activities. Blocking a view has creating privacy as its corollary.

This objective can be accomplished by installing one or more shrubs or trees to interrupt a sightline between a favored spot on the landscape and the undesired view, or between a spot where privacy is wanted and a place where an off-site viewer might be.

This strategic act will succeed most quickly if the renovator installs large plants, but that can be very expensive. The garden renovator should be patient enough to install plants of affordable size, and savvy enough to select shrubs or trees that are fast-growing but otherwise garden-worthy.

Resist any inclination to install a shrubbery wall to block the view to and from the public sidewalk and street. This landscaping device announces, “A recluse lives here.” Adjustable window coverings are better alternatives.

Frame a Desired View

The viewshed of some homes might include a field or forest or mountain or ocean or some other scene that pleases the eye. It might be the natural environment or a built structure. In such happy situations, the first landscaping objective should be retain or reveal the view. This might require removing poorly placed trees or shrubs, and not installing plants that would grow to obscure the view.

The second objective should be to develop landscaping that draws attention to the viewshed and to its best features. This might involve framing the view from a selected observation area, which might be inside the residence or on a deck or patio. Just as a picture frame separates a picture from it surroundings, carefully positioned trees can highlight a desired viewshed.

In time, an undesired view could become unobjectionable, and new construction could block a desired view. Whatever happens, your view shed rights stop at the property line, so manage your landscaping accordingly.

More

Trees that are fast-growing but otherwise garden-worthy.

Proving once again that the Internet provides access to a vast store of information, Clink this link to the website Fast-growing Trees. There are three pages of trees that are fast-growing and suitable for USDA Hardiness Zone 9, which includes the Monterey Bay area.

When selecting a fast-growing tree to install in your particular garden, consider (in addition to the hardiness zone) the mature height and width of the tree, appearance, and any other factors that are important to you. Some of the trees listed on the Fast-Growing Trees website are too large for a smaller property, and some are too small to be useful as a screen of an undesired view.

Here is a link to This Old House on Fast-Growing Shade Trees.

In my own garden, several years ago I planted three seedlings of Pittosporum tenuifolium fairly close together, to screen a nearby property. The seedlings, which had sprouted in another part of the property, grew rapidly to over 30 feet, which is taller than I expected, based on the available information. This shrub (also called P. nigricans, because of its dark branches) is evergreen and trouble-free, so it has been a very successful screen.

Here are those three large shrubs in my garden. doing a good job of concealing the house beyond (click to enlarge).

 IMG_0302

Finally, here is a link to SF Gate for more information about this large shrub.

 

Selecting a Landscape Tree

“The best time to plant a tree is twenty years ago. The second-best time is now.”

This is one of many hoary bits of wisdom about gardening. Instead of reviewing more such bits, let’s consider how to select a landscape tree during this year’s dormant period.

The New Sunset Western Garden Book (2012)—always a useful reference—lists four categories of garden trees that not yield edible fruits: patio, shade, flowering and fall foliage.

Patio trees are primarily ornamental, and relatively small and free of troublesome behavior.  Shade trees are larger than patio trees, and typically deciduous. Flowering trees and fall foliage trees also provide shade, but they are selected primarily for their ornamental value.

Landscape trees, depending on size, could be dug as bare root specimens, grown in a plastic container wooden box, or dug and “balled & burlapped.” The larger specimens can be expensive and very heavy to manage, but desirable for achieving an immediate effect in the garden.

Once the gardener has decided on the landscape purpose of the tree and its size at the time of purchase, there are three major criteria for selecting a specific tree.

First, know the tree’s mature size and ensure that it will not outgrow the location you have in mind. The most common error in selecting and planting a tree is to locate it where it eventually will grow to become unwelcome. It might crowd a pathway or driveway, or even the residence. Its might harm other plants by blocking the sunlight with its leaves or absorbing the available moisture with its roots. Choose a tree that will be a good neighbor.

Second, for containerized trees, confirm that the roots have had ample room to grow normally. A tree’s roots should fill no more than 50% of the container; otherwise, the tree could become root-bound, with a long-term threat to its life. I once had a tree service install a large Santa Cruz Cypress (Cupressus abramsiana), an endangered species, only to have it topple months later during a mild windstorm. I discovered that it was severely root-bound, so that its roots could not anchor the tree effectively. Before buying a tree, examine its root structure by pulling the tree from its container.

Thirdly, ensure that the tree’s future location has at least six hours per day of exposure to sunlight, which almost all trees require for health and normal growth. I planted two identical Chilean Myrtle (Luma apiculata) trees, one in full sun, and one too close to an American Sycamore (Platanus occidentalis). Today, the tree growing in the sun is about three times the height of the other tree.

Choose your new landscape tree with care!

More

The April 2014 issue of Fine Gardening magazine (already on the newsstands and in libraries!) includes an excellent article on this topic. “How to Buy a Tree” by Ed Gregan presents a most thorough discussion of problems that might be encountered with a nursery tree.

I hasten to add that reputable nurseries and garden centers won’t offer trees with significant shortcomings. The owners and managers of well-run retail garden outlets are good people who respect plants and gardening.

Still, it’s possible for a problem to slip through and you could take home a tree that won’t thrive as you, the original grower and the tree itself would prefer. The most common problem is a tree that has become root-bound, after sitting in the garden center or nursery too long. This condition obviously could develop while the manager was not looking!

Ed Gregan’s article is not available online (except for Fine Gardening subscribers), so I can only list his bullet points (below), but you’ll need to read the article for the full story.

  1. Ensure grant points are smaller than a dime
  2. Walk away if there are wounds
  3. Pull off the pot to assess the roots
  4. Strive for a single straight leader
  5. Check under the trunk protector
  6. Look for signs of trouble
  7. Watch out for “coat hangers”
  8. Avoid poor crotches
  9. Avoid even numbers for multistems
  10. If the flare is too high or too low, the tree is a no
  11. Give the ball a thorough inspection
  12. Check for even spacing with clumps