Rain Gardens – Advanced Water Conservation

Most gardeners have learned that large percentages of residential water usage occur outdoors, mostly as a result of irrigating lawn grass and other plants, and have adopted water-saving practices: replacing thirsty lawn grass with naturally drought resistant perennial plants, especially California native plants, using efficient drip irrigation, and mulch. These strategies involve relatively low expense, depending on implementation.

Some gardeners have gone to the next stage of water conservation, which includes water catchment and grey water recycling. These strategies require equipment, and its installation, both of which could lead to some initial expenses. A 5,000-gallon water tank, for example, would be a substantial investment, but one pays off through long-term water savings or even fire protection.

Today’s column introduces percolation ponds as another stage of water conservation.

When we are fortunate enough to have rain, much of the water from roofs and paved areas runs to storm drains, which in the Monterey Bay area lead eventually to the sea. An efficient storm drain system avoids flooding, but often delivers pollutants into the ocean. A better approach is to direct the runoff to the soil, which filters the pollutants and leads the water into the aquifer.

This approach involves the development of a percolation pond, which is simply a low area that collects and holds runoff so that it percolates into the ground.

The principal objectives for percolation ponds are to filter runoff to minimize pollution, recharge local groundwater, and conserve water.

To include a percolation pond in your garden, find a naturally occurring low area (or create one) that is at least ten feet away from your home and any existing septic field. This separation is needed to avoid having water migrate towards your foundation, or to interfere with any utilities close to the house.

Rain Garden - Sentinel

A rain garden by a driveway in Pacific Grove. Credit Dona Johnsen Landscape Archietcture

 

gi_raingarden

A rain garden away from the (east coast?) residence. Credit: EPA:gov

 

The percolation pond should have good drainage, so that it holds water for no more than forty-eight hours. A retention pond, by contrast, holds water for longer periods, and could be designed as a water garden or bog garden.

Determine the surface area of the percolation pond to reflect the surface area of the capture area and the soil type. For example, multiple the surface area of your roof by 20% for sandy soil, 33& for loamy soil, and 45-60% for clayey soil. If you are creating a percolation pond, the bottom layer ideally should consist of about 60% sand, 20% compost and 20% topsoil. This composition would provide effective filtering of the runoff.

Then, adjust downspouts or a sump pump outlet to direct the water into the percolation pond. Depending on the situation, a bioswale could be used to direct the runoff to the percolation pond. A bioswale is a drainage course with gently sloped sides (less than six percent) and filled with vegetation, compost and/or riprap.

In areas that receive regular rainfall, the upper layer of the percolation pond can be planted with deep-rooted perennials, which can flourish under occasional deep soaking, followed by relatively dry periods. These features are called “rain gardens.”

In California, where we need to protect and restore our aquifers, and have current drought conditions, the upper layer might emphasize decorative stones, which can slow the flow of water that might otherwise overflow, and promote percolation. California native plants, once established, would do well in a percolation pond, and also provide both an attractive appearance and environmental benefits. Continue reading

Gardening during Drought

Californians are agonizing over our severe drought and its probable future. Those going through the greatest stress are homeowners maintaining verdant lawns and gardens in southern California’s deserts, farmers using 80% of the state’s surface water, and policy makers working to move the state’s burgeoning population toward life styles and businesses that use our limited water wisely.

This will be a lengthy slog.

The good news for Monterey Bay area residents is that we have already made excellent progress in reducing water usage to the target level, which is 25% below the usage of February of 2013.

We all need to conserve more to reach that target, but not nearly as much as people in southern California, especially in desert areas, where water usage is double the state average.

Growing grass and common perennial plants in sand unavoidably requires unusual cultivation methods, including lots of water. Such gardening ignores the first rule of gardening: right plant in the right place.

The primary strategy for drought-tolerant gardening, then, is to grow plants that are native to your own patch of land. The corollary strategy is to grow plants that are similar to plants that are native to your site. For the Monterey Bay area, this means plants from the world’s regions with a summer-dry climate. These include (if you need yet another review) the Mediterranean basin, South Africa, Chile’s central coast, Australia’s southwestern coast, and of course, much of California, especially the central coast region.

Keep in mind that each of these regions includes a range of microclimates, so it is still wise to know the particular conditions within your garden, and to favor plants that thrive in those conditions. That is the crucial method for low-maintenance gardening.

I have just received Sunset’s latest book, which addresses this point in a timely, effective and attractive manner. The Sunset Western Garden Book of Easy-Care Plantings has chapters on Gardens, Beds and Borders, Succulents, Groundcovers, and Containers. Other sections provide an overall introduction and seasonal tips.

Sunset Book Cover

Click to Open

 

Kathleen Brenzel edited this book, and has edited several earlier books that merit a prominent place on California gardeners’ bookshelves. This new book includes advice from such experts as John Greenlee and Robin Stockwell, who know all there is to know about grasses and succulents, respectively, and who have shared their knowledge with gardeners often over the years. During Robin’s 2014 Succulent Extravaganza, for example, I enjoyed John’s presentation of a companion planting of grasses and succulents.

California’s drought results from the combination of several factors: cyclical weather patterns, climate change, population growth, and agribusiness expansion. It is a complex picture, to be sure, and avid gardeners need to adapt to changing conditions.

My initial scan of The Sunset Western Garden Book of Easy-Care Plantings impresses me as a good source of guidance and inspiration for that adaptation. I welcome the opportunity for learning from each chapter, and anticipate enjoying the experience, which surely will motivate even more sustainable gardening.

Small Gardening

The gardening world has been buzzing about small gardens. Interest in this topic might reflect a trend toward a preference for smaller properties or a growing desire among gardeners to limit the time and energy they commit to gardening.

A small garden could be the entirety of a small property or an area within a large property. A large property might include several small gardens (sometimes called “rooms”) or one small garden plus undeveloped space, or something between those extremes.

In either case, the goal for small gardening should be quality gardening.

“We would do well to follow a common rule for our daily lives—do less, and do it better.” — Dale E. Turner

(I don’t recognize the person who said that, but I agree with the sentiment.)

When developing a small garden, all the usual criteria for plant selection and cultivation apply: ensure that the soil is fertile, friable and well drained, and choose plants that are appropriate for the garden’s climate, sun exposure and prevailing winds.

Basic landscaping design ideas are important in a smaller garden.

  • Repeat a limited number of plant varieties, and just two or three flower colors. A random collection of plants and a rainbow of blossoms can be confusing, in a design sense, while repetition provides a coherent an ultimately more pleasing effect. Carefully planned combinations of foliage colors also can work well, especially when planting succulents, which are available in many interesting colors.
  • Place the taller plants in back. This is my favorite — and simplest —landscaping design concept. Following it requires care in plant selection. The first level of research is to read the label, which should indicate the plant’s mature height and width. If necessary, use the plant’s botanical name to look it up on the Internet, or in Sunset’s Western Garden Book, or another plant reference book.

If a plant grows beyond your expectations, move it to a more appropriate location. If it’s too big to move, it may be time for “shovel pruning.” Replace that overgrown treasure with a better choice.

  • Use curves and different elevations to add interest. If your small garden space is basically an uninteresting flat rectangle, consider introducing a curved path around a naturalistic mound.

In addition, three broad guidelines come to mind.

First, specify a theme beyond “small size.” The garden might focus on a genus (rose, iris, clematis, etc.), a category of plants (succulents, white blossoms, herbs), a plant community (California natives, South African bulbs, aquatic plants) or any other theme of interest. A theme provides coherence to the garden and a systematic approach to plant selection.

Second, provide a story line for visitors. The garden planner could guide a visitor’s attention by establishing a focal point: a well-placed, exceptional plant, a piece of garden art, or a water feature, etc. After that initial impression, the gardener or discrete signs might encourage a visitor to examine a series of specimen plants. A rose garden, for example, might showcase several hybrid teas or species roses for comparison.

Finally, plan the maintenance of the small garden for close inspection. No garden looks good when unkempt, but a neglected small garden can be particularly unsatisfying to both the gardener and the visitor. While fallen leaves, a forgotten watering hose and a few weeds can be tolerated in a large, sprawling garden, a small garden should be raked and pruned and tidied regularly. By virtue of being small, it should also be manageable.

The small garden is to a large garden as a sonnet is to free verse.

A small garden can yield big enjoyment!

Garden Decor

Gardens can be more than artful displays of plants: they can also include arts and crafts that reflect the owner’s tastes, interests and creativity. Collectively, such items comprise the garden’s décor.

The selections that we might encounter in gardens range from stunning works of fine art to found art to  “junktique,” with items such as plants growing in worn-out boots. This range could be defined in terms of cost.

For many home gardens, the most prominent décor consists of plant containers, which offer many opportunities for artistic expression. The more successful of these expressions present an interesting relationship between the container and the plant(s) it contains.

The less successful involve uses of nursery cans, which are typically black plastic. Such containers could be seen as an exercise in utilitarianism: they are valued for their usefulness and low cost.

Gardeners often acquire their décor often on the open market, but they gain the most satisfaction by making their own pieces. This requires creativity but doesn’t necessarily require artistic skill.

As an example, this “garden path medallion,” one of four in my garden, is a unique product that required care to build, but inexpensive materials and only a modicum of artistry. The medallion is four feet in diameter. My rabbit, Harvey, is sitting in to indicate the scale.

Pathway Medallion

Click to Enlarge

An important component of this project is a circular strip that retains the circle of bricks. I found this product on Amazon.com, marketed as the “EasyFlex No-Dig Tree Ring Kit.” This strip retains the bricks with a 1.5-inch high edge, low enough to hide under the pathway surface.

I purchased common bricks for the four medallions, each of which required 34 bricks. We installed the steppingstone and bricks in a bed of decomposed granite (also called path fines), which has angular grains that lock into a firm yet permeable surface. Beach sand has more rounded grains that stay too loose for such applications.

Common bricks are too large to form a tight ring around the steppingstone, so we used black, oval-shaped stones, sold as Mexican pebbles, three-to-five inches long. We installed them on edge, and used a rubber mallet to level them with the steppingstone and bricks. The last step was to sweep decomposed granite into the gaps and water it to settle it around the hard materials.

The costs for each medallion include the tree ring $10; 34 common bricks: $34; Mexican pebbles $16; cast concrete steppingstone $20, more or less, for a total of about $80 for a near-permanent feature.

Decomposed granite costs $40-to-$50 per cubic yard, but the amount required for this project would depend on the length, width and depth of the pathway.

A relatively new product for filling the gaps between stones is polymeric joint sand, which includes a water-activated polymer that forms impermeable joints. This product, available from masonry services, costs $15-to-$20 for a 60-pound bag.

For pictures of many do-it-yourself garden arts and crafts projects, visit Pinterest.com and search for “steppingstones,” “garden crafts,” “garden arts” or related topics of personal interest. You might be inspired to adapt someone else’s idea or come up with your own unique creation.

However you proceed, décor could bring interest to your garden and provide creative opportunities fvor the gardener.

***

Because we are bulb-planting season, I will share a link with a recently discovered webpage, Tulips in the Wild, that presents a map of Europe and the Middle East, showing where various species of tulips grow, with photos of each species in its natural habitat. This website was developed by the Amsterdam Tulip Museum and the U.S. bulb seller, Colorblends. Browse to <tulipsinthewild.com> and click on “Interactive Map.”

If you enjoy tulips, this page provides a fascinating and informative display of the origins of many different tulips. If you thought that tulips come from the Netherlands, the truth is that only hybrid tulips come from growers in Holland. This webpage shows the real origins of this popular garden plant and could suggest a new idea for plant collecting.

Low-Maintenance Garden Themes

Designing a garden bed around a theme yields practical and aesthetic benefits.

The aesthetic benefit of thematic garden design rests on the relationships among the plants: they are linked by being members of the class defined by the theme. In that respect, a thematic group is more coherent, aesthetically, than the ever-popular “grab-bag” approach to plant selection.

The practical benefit is a plan for selecting plants from the hundreds of thousands of available varieties. Once the gardener has chosen a theme, he or she has reduced the universe of possible plants to consider. This one action narrows the selection task and supports close evaluation of options.

A garden design theme is simply a concept to which plants relate. This definition embraces a very wide range of possible themes, which could be a single color or combination of blossom colors; a plant genus, e.g., rose, iris, daffodil; size, e.g., miniatures; bee-friendly, etc.

For today’s topic, consider a progression of four themes for low-maintenance gardening.

Theme #1: Zone-appropriate Plants. Every gardener should know the U.S. Department of Agriculture’s Plant Hardiness Zone in which his or her garden exists. The Monterey Bay area is in USDA Zone 9b, where minimum temperatures are in the 25–30 degree range; plants marked for Zone 9 should survive cold spells in that range. A great many plants are that hardy, so this theme excludes only plants that are vulnerable to cold and therefore high-maintenance. Nurseries also use UCDA zones to indicate the preferred zone for given plants. Plants that are rated for Zones 10 or 11 usually will thrive best in very warm climates, not in Zone 9.

Theme #2: Mediterranean Climate Plants. These are plants that have evolved to grow well in the world’s areas that have dry summers and moderate winters. These areas (again) are native to the central coast of California, the central coast of Chile, the southwestern coast of Australia, South Africa and the Mediterranean basin. A large number of plants are suitable for this theme, but this category still is significantly smaller that Theme #1.

Theme #3: California Native Plants. This theme is within Theme #2, of course, but it stands apart from the others because includes plants that are both suitable for the Mediterranean climate and the soils and fauna of this state. Soil chemistry and symbiotic relationships with birds, mammals, insects and microbial life contribute significantly to the growth of plants, and, ultimately, the success of the gardener.

Theme #4: Native Plant Communities. A great variety of plants are native to California, and many have evolved to grow best in specific environments within the state, and in communities with specific other plants. An oak woodland plant community is certainly different from one that occurs naturally on coastal bluffs and cliffs. For the ultimate in low-maintenance gardening, adopt a thematic design for a California native plant community that would be appropriate for your garden setting.

Consider a thematic design for each garden bed or each large area of your garden. Plant selection will transform a random process to a purposeful activity.

Books for Thematic Designs

Zone-appropriate Plants
The New Western Garden Book (Sunset, 2012)

Mediterranean Plants
Plant Life in the World’s Mediterranean Climates (Dalman & Ornduff, 1998)

California Native Plants
California Native Plants for the Garden (Bornstein, Fross & O’Brien, 2005)

Native Plant Communities
Designing California Native Gardens: The Plant Community Approach to Artful, Ecological Gardens (Keator, Middlebrook & Faber, 2007)

 

Planning Garden Stairways

My garden includes a slight slope with a few stairs, made with 8” x 8” x 48” wooden highway ties. Earlier, garden stairs might have been made with railroad ties, which were often soaked in creosote as a preservative. Today, highway ties are pressure-treated with chemical preservatives, many of which are too toxic to be used near edible plants.

Happily, my short flight of aging stairs was not treated with a preservative, but consequently it is deteriorating and needs replacement. Wood is suitable for stairs that do contact soil, but in this case I will avoid rot by using flagstones or other natural stone. There are manufactured stone-like materials that also are available for such a project.

When planning garden stairs, first determine your preferred dimensions for the risers and treads. A six-inch riser with a fifteen-inch tread is a recommended combination, but other combinations also can work well. A steep flight of stairs might have seven-inch risers and eleven-inch treads, while a gentle flight might have four-inch risers and twenty eight-inch treads. See on gardening.com for the range of other good combinations.

Then, use a straight board and a carpenter’s level to measure the change in level from the bottom to the top of the slope. For a longer slope, use a garden hose, taking advantage of the fact that water seeks it own level. Hold the hose in a U-shape, with one end near the top of the slope and the other end near the bottom. Fill the hose with water, and adjust it so water is at the opening of each end. When this condition has been met, the two ends will be at the same elevation, and the distance of the lower end to the ground, minus the distance of the upper end to the ground equals the change in level. See ongardening.com for an illustration of this method.

Divide the change in level by your preferred height for the riser to determine the number of steps needed for that particular slope.

Then, measure the horizontal distance from the bottom of the slope to the top. Your preferred dimension for the tread times the number of stairs should equal that distance. If it does not, modify the riser and tread dimensions (using one of the good combinations) or include a curve in the flight of stairs or reshape the slope.

The width of the stairs is the next design issue to be addressed. The narrowest width could be two feet, which might be sufficient for a utility stairway. A one-person stairway should be four feet wide, which is generally considered the minimum for a garden path. A two-person stairway should be five feet wide.

Wider stairways, in scale with the landscape, can provide a visually striking appearance. This stairway at Les Quatre Vents, an estate near Quebec, is designed for grand entrances. (Click to enlarge)

Grand Staircase

Staircase at Les Quatre Vents, near Quebec, Canada

Continue reading

Gardens as Tools

Following recent surgery, I felt too fatigued and sore for even light gardening. Those limitations lasted about one week, after which I could again put in several hours on easy—and overdue— tasks: weeding, installing small plants, pruning, all of which helped a lot in my recovery.

This episode stimulated thoughts of the garden’s many functions beyond pleasing the eye, feeding the stomach and providing regular light exercise.

Without minimizing the direct benefits of ornamental and edible gardening, consider the types of therapeutic gardens: healing, meditation, contemplation, and restorative.

“Healing” means helping individuals to overcome physical, mental, emotional or spiritual challenges.

“Meditation” involves deepening personal knowledge and attaining inner peace.

“Contemplation” involves thoughtfully examining issues larger than oneself, perhaps in a religious or mystical manner.

“Restoration” refers to returning to an ideal or normal state from a stressed or agitated state, or from boredom or difficulty in focusing.

A garden designed to help individuals to overcome physical challenges is described as an accessible garden. The design typically emphasizes raised beds, tall enough to provide easy access to the gardener who cannot kneel, or finds it difficult to do so. (Rising from kneeling could be just as challenging.) There are also convenient tools, e.g., rolling seats, tools with long handles, telescoping pruners, for gardeners who have grown to be less than spry.

Other kinds of accessible gardens are designed for gardeners with partial or complete loss of sight, emphasizing blossom fragrance or plant texture over appearance, to favor smell or touch.

No garden, however accessible or well intentioned actually effects any healing or restoration. Only the gardener who desires to be healed or restored can achieve such outcomes. In this perspective, the garden is not the cure, only the gardener’s tool.

The focus on the gardener is the same for meditation and contemplation gardens, which offer only nature’s calm environment to invite the gardener to forget for the moment personal stresses and the busy world’s demands, and to consider issues greater than “why snails?”

There’s one more type of therapeutic garden: the motivational garden, which helps those who may be bored or having difficulty in focusing.  Once we have begun gardening, and experienced the satisfaction of seeing plants grow under our hands, even a brief visit to the garden stimulates the urge to pull a weed, deadhead a faded blossom, or move a misplaced specimen to a better spot.

Gardens are valuable tools for many special purposes; many gardeners find them therapeutic on all occasions.

More

The American Horticultural Therapy Association provides its definitions and positions regarding therapeutic gardening.

The American Society of Landscape Architects offers an interesting essay, “The Therapeutic Garden— A Definition.”

Pinterest (which collects photos on various topics from many sources has several unorganized groups on topics related to therapeutic gardens. A search on “horticultural therapy ideas” yields this collection, which demonstrates the wide range of ideas that people associate with “horticultural therapy.”

 

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.

 

Behind Schedule in the Garden

The garden does not wait for the gardener, but goes about growing, reproducing, aging and eventually dying whether or not the gardener meets the schedule of seasonal tasks.

My garden has proceeded this year on its natural cycle. As the weather has warmed, even the plants for which I should have cut back last year’s growth are producing abundant new growth

Salvias exemplify this failing. Best practice with salvias is to cut them to the ground in the late winter or very early spring, when new growth first appears. This practice rejuvenates the plant, and gives it a youthful look. When the pruning is done too late, it is very difficult to avoid cutting off the new growth and setting back the seasonal growth.

I cut back a few of the salvias in my garden, but left many more with their tired branches from last year.

Fortunately, perennial plants really do not depend on punctual gardeners. Salvias perform better when treated well, of course, but they will survive nicely even when neglected.

I was able to prune my roses at the right time. It is possible to let rose shrubs grow without annual pruning during the dormant season, but they will have a more compact form and produce more blossoms when cut back about one-third each year.

Fruit trees are another matter. Happily, I pruned my apple trees in a timely way: I cut back last year’s growth just before blossoms appeared on the trees. There are just four dwarf apple trees in my garden, but skipping this annual task would allow sprawling growth and reduce the yield.

I did not, however, spray my trees as recommended to discourage codling moths. I did read about the life cycle of those pests, and made life a little harder for the over-wintering larvae by raking the mulch away from the base of the trees.

Weeds also are responding well to our limited rain and the warming weather. They are growing very nicely! I haven’t identified all the several weeds that make my garden their home, but I can always spot the bright yellow flowers of sourgrass, which expands its territory in my garden each year.

Wikipedia (always helpful) has this comment about sourgrass: “Indigenous to South Africa, Oxalis pes-caprae, the ‘Bermuda buttercup,’ is an invasive species and noxious weed in many other parts of the world, including the United States (particularly coastal California)…”

Ideally, gardeners should pull this weed when it first appears, before it produces countless tiny bulbs. Sadly, I am behind schedule again this year.

This experience yields clear lessons for gardeners:

  • Strive to keep pace with Nature’s rhythm
  • Appreciate the ability of plants to thrive despite neglect, and
  • Take satisfaction in the seasonal tasks you do complete.

Enjoy your garden!

More

Several books on year-round gardening are available through your public library, your bookstore or online. For example, a search of the Amazon.co website for “gardening year-round” yields 45 pages of books to consider. Many of the books listed focus on edible gardening; several also include ornamental gardening.

Before investing your time or money in a gardening book, make sure that it has information for your gardening environment. The most useful gardening information for gardeners in the Monterey Bay area will be specific to USDA Plant Hardiness Zone 9. Information in books oriented to “northern California” or “Pacific Northwest” will need interpretation for gardeners in Zone 9. Books intended for other parts of the United States or the world could still be helpful, but should be treated like exotic materials.

Still, given that awareness, some classic books on year-round gardening written by English authors can be very much worth reading. Examples, include books by Vita Sackville-West, Beth Chatto and Christopher Lloyd.

Whether written by American or English gardening experts, the date of publication is not important: Nature’s seasonal patterns have not changed significantly.

Here are suggestions:

The Four-Season Landscape: Easy-Care Plants and Plans for Year-Round Color (A Rodale Garden Book) (1994), by Susan A. Roth (Author)

Golden Gate Gardening, 3rd Edition: The Complete Guide to Year-Round Food Gardening in the San Francisco Bay Area & Coastal California (2010), by Pamela Peirce (Author)

Gardener to Gardener: Almanac & Pest-Control Primer (2000), by Vicki Mattern and Fern Marshal Bradley (Eds)

A Yardscapes Year: Ideas and Plants for Bay Area Gardeners (1999), by Mia Amato

The Western Gardener’s Journal: A Three-Year Almanac (1998), by Margaret Moulton