Color in the Winter Garden

Posted on February 5, 2016 by tomkarwin

A good practice is to walk through your garden occasionally to see what is succeeding, and what might need changing. It’s rewarding to visit your plants in the spring, but the winter months (now) are when we look for dormant season instances of attractive color, form or fragrance.

In the Monterey Bay area, the dormant season brings nothing like the severe conditions experienced in some other parts of the United States, but our gardens still rest at this time, and might present only limited interest.

It doesn’t have to be that way! There are many plants that can enhance our gardens while other sleep, when we plan for all season interest.

A first step is to take note of plants that are already in your garden, and looking good right now. They might be providing attractive blooms or interesting foliage, taking the center of attention while others have dropped their leaves or died to the ground.

You could supplement the tour of your own garden with a walk through your neighborhood to see what looks good in nearby gardens. That approach automatically identifies plants that would thrive in the climate and soil conditions of your garden. It can also be a good excuse to meet new people, to ask them about their gardens.

My garden, while not a true all-season display, still has several plants that are attractive during the winter months. For example, succulent plants, which have done well during our drought period, can maintain their appearance during dormancy.

I recently renovated a small bed of Mexican succulents, and the plants are looking good. They will produce blossoms later in the year, but the forms and colors or their foliage works well year-round. The recent addition of a large Talavera bowl, recently added, serves to mark the bed’s Mexican theme.

Talavera pottery, offered by many garden stores, is a style of glazed ceramic pottery that dates to the Italian Renaissance. Authentic Talavera items are from the Mexican city of Puebla and nearby communities, but imitations (which includes my own piece) are widely available. Imitations from other parts of Mexico are properly identified as Maiolica, which refers to the decorative style.

Other plants that are starring during the winter include a Purple Lilac Vine (Hardenbergia violacea), an Australian native, now covered with small violet flowers; an enormous Candelabra Plant (Aloe Arborescens) from South Africa, blooming later than others in the area, and a favorite, a Variegated Winter Daphne (Daphne odora ‘Aureomarginata’), which offers both colorful evergreen foliage and a sweet fragrance that highlights the season.

Daphne odora ‘Aureomarginata’

When provided good drainage and afternoon shade, daphnes are reliable performers for years until they suddenly and without apparent cause, give up. An older specimen recently showed arrested development: flower and leaf buds simply didn’t mature for months. After quizzing three knowledgeable friends, without success, I removed the plant (making space for another fuchsia). By this time, I already had three replacement daphnes growing nearby, so I still could enjoy the wafts of fragrance this year.

Prepare now to bring new interest to your garden for next winter with more seasonal bloomers and evergreen foliage, either adding specimens of existing plants that you like or bringing in good performers that you have seen in nearby gardens. Winter gardens can be very pleasing environments.

A quick Internet search or a visit to your local library or bookstore could lead to useful lists of winter-blooming plants. For example, one good source of information is Dan Hinkley’s book, Winter Ornamentals.

Adding Unexpected Plants to Your Garden

Posted on January 9, 2016 by tomkarwin

This column presents a case study of adding an unexpected and unfamiliar plant to one’s garden.

A friend gave me a plant that had outgrown its container, and no longer had a place in its previous home. My friend didn’t have a name for the plant, but a neighbor’s garden has a related species: the photo shows much longer leaves than my gift plant, and the potential to grow rather large.

Dyckia

I had never grown a plant like this one, so I was immediately interested. Here is a suggested intake process.

First, inspect the plant visually to check that it is healthy and free of disease or pests. This plant had some dieback from normal aging and outgrowing a large container, but otherwise looked healthy. I gladly accepted the gift.

Identification should be the next priority. I had seen this plant in four-inch pots, and knew it as a Dyckia, but learning the genus and species of a new plant can be challenging. This plant doesn’t appear in Sunset’s Western Garden Book, a convenient reference. In such cases, asking other gardeners or garden center staff can be the best strategy.

Then, examine the plant’s size and characteristics. This Dyckia develops several rosettes eight-to-twelve inches in diameter. Each rosette is comprised of many thin leaves up to eight inches long, with very sharp terminal spines and numerous sharp teeth on both sides. (My neighbor’s magnificent Dyckia has leaves up to two feet long!) The plant is attractive, but neither welcoming nor easily handled!

Considering both this plant’s mature size and hazards, I concluded that it should be should be three feet from any walkway, but still close enough to appreciate its intricate leaf structure.

Also, it should not be under a tree, as it would be difficult to groom dropped leaves from the Dykia’s spiny cluster.

Then, learning about the plant’s cultivation needs will guide planting and future care. An Internet search for “Dyckia” brought me these websites: Wikipedia; Bromeliad Society of Houston; Yucco Do Nursery; Annie’s Magic Garden; and Dyckia Brazil.

Dyckias, I learned, are native to Brazil, members of the Bromeliad family, and related to pineapples (Ananas comosus), Puyas, Tellandsias, and Bilbergias. There are some 158 species of Dyckias.

After comparing my specimen’s appearance with others on the Internet, I concluded that it is D. fosteriana, which is a popular species. This plant hybridizes easily in nature and in human hands, so many cultivars are available. Confident identification requires a specialist.

The Dyckia lacks internal water storage tissue, so it’s not a true succulent, but it will go dormant in response to a lack of moisture. It prefers full sun but will manage partial shade, and has exceptional tolerance for freezing weather. It is pest-free, although snails will nibble at tender flower shoots. Generally, the Dyckia is a sturdy and trouble-free plant.

Dyckias reportedly do not like transplanting during the winter, but I proceeded still to separate and pot up six offsets (”pups”) for gifts to others, and to put my new plant in the ground. I’ll learn how well it responds.

My garden lacks a bed for Brazilian plants. I accommodated this unusual new plant by redefining my existing Chilean bed as Chilean/South American.

Avid gardeners should welcome unexpected, unusual and attractive gifts to their gardens. A systematic process can help to place the plant well and to provide the care needed for its success. New plants are gardening adventures!

Twelve Ways to “Plant-Mass”

Posted on December 25, 2015 by tomkarwin

An important guideline for amassing plants in your garden is to plant when seasonal rains will water the plants as the establish roots and prepare for blooming in the spring. So, a good time to add plants to your garden (or to find a late gift) is right now.

Here are twelve ways to succeed in that enterprise.

Plan to fill an existing space in the garden. Impulsively buying plants that catch your eye in the garden center can result in specimens that are too large or too small for spaces that need filling, or won’t complement plants next to those spaces.
Focus on plants that will add to your landscape style or theme. There are many alternatives to randomness in garden design. An explicit theme or style in your garden provides direction in the hunt for new plants, and adds coherence to the look of the garden.
Choose plants that will thrive in your garden’s environment. Most important is your U.S. Dept. of Agriculture climate zone, but also consider elevation, sun exposure and soil type.
Jade Plant (Crassula argenta) in a one-gallon nursery can
Select plants of an appropriate size for the spot where they will grow. A common error is to install a plant that will outgrow its location.
Look for plants that are pest resistant. With fuchsias, for example, a good choice would be a variety been bred to resist the Fuchsia Gall Mite (Aculops fuchsiae), a pest that’s difficult to control.
The logical corollary is to examine plants that you might buy to check for any evidence of “livestock.” The symptoms (e.g., chewed leaves, creepy-crawlers or their eggs on the underside of leaves) are usually unmistakable, but if you have any uncertainty, choose a plant that’s symptom-free.
Similarly, look for plants that are disease resistant. Several varieties of roses are both beautiful and resistant to powdery mildew and black spot. Why would you want to struggle with those diseases?
Again, before buying a plant, check for any sign of disease, or anything other than good health. Garden centers screen their plants diligently, to protect customers and their own reputations, but problems can be missed. This is most possible with amateur plant sales.
More and more, gardeners prefer plants that are free of toxic synthetic chemicals. Growers are beginning to label plants that have been grown without the use of neonicotinoids (“neonics”), for example, which appear to be harmful to bees. If the label doesn’t give assurance, ask!
To minimize your plant-buying expense, favor the garden center’s smaller plants. They should be well rooted, rather than freshly transplanted. In your garden, they will grow quickly to reach the size of more expensive plants.
On the other hand, to achieve an immediate effect, favor the larger plants. You will be paying the nursery for caring for the plant for months or even years, but the results may be worth the cost. An added benefit is seeing a well-grown plant’s structure.
Before buying a plant, especially one that fills its container more than others, check for healthy roots. Gently pull the plant from its container to examine roots for healthy color (usually white) and ample space in the container. Plants left too long in a container become root-bound, which can hamper their growth. On the other hand, such plants often could be divided into two or more for the price of one.

Adventuresome Gardening

Posted on November 13, 2015 by tomkarwin

Regular readers of this column know of my interest in plants from the world’s summer-dry climates, also called the Mediterranean Basin regions. Many plants from these exotic regions will thrive in the Monterey Bay area, and provide attractive and exciting alternatives to the garden center’s humdrum horticulture. Cultivating such plants is the enterprise of adventuresome gardeners and seekers of botanical thrills.

There are countless examples of such plants to be discovered among the selections of mail-order nurseries, either in published catalogs or online. To be fair, local garden centers also might have a few offbeat offerings; it’s worth asking the staff to mention any unusual plants.

One candidate for a featured position in the landscape is the Puya, which is one of about fifty-seven genera in the Bromeliad family. Just about all bromeliads are native to the tropical Americas. About half of the species are epiphytes (growing on air and rain), some are lithophytes (growing on rocks), and the rest are terrestrial (growing on earth). The most familiar of the terrestrial bromeliads is the pineapple (Ananas comosus).

Another terrestrial bromeliad is the Puya. This genus includes about 210 species, several of which are native to Chile, where they have the common name chagual.

One of the Chilean Puyas is the Blue (or Turquoise) Puya (P. berteroniana). This plant grows a flower spike about six-to-ten feet tall, and has exceptional landscape value because of its extraordinary 1.5” waxy, metallic blooms of an unearthly emerald-turquoise color, with contrasting bright orange stamens. The blooms hold blue, syrupy nectar that attracts hummingbirds, bees and other pollinators.

The Blue Puya can be found in some public gardens. I viewed several fine specimens, and took this photo, about one year ago, in the Australian National Botanic Gardens, in Canberra.

Locally, the Blue Puya is in bloom now at the UCSC Arboretum. The blooms do not last long, so to see one of nature’s most extraordinary flowers, visit the UCSC Arboretum soon. For information and pictures, visit arboretum.ucsc.edu/ and click on “What’s Blooming.”

The Chilean bed in my garden includes two quite young examples of this genus: a Blue Puya (P. berteroniana) and a Silver Puya (P. coerulea). These are slow-growing plants, now years away from blossoming in my garden. While they are not yet pleasing my eyes, they are already trying my patience (a little) and piquing my imagination.

Annie’s Annuals lists nine Puya species, but current availability includes just three. Similarly, the wholesale nursery San Marcos Growers lists eight Puya species, with just three currently in production. Your local garden center could special-order plants from these nurseries, or another preferred source. Search the Internet by botanical name for information to share with garden visitors.

You certainly can keep your garden’s tried and true selections, but consider adding exotic plants to enrich your landscape.

Exotic Bulbs for Spring Bloom

Posted on November 7, 2015 by tomkarwin

As we proceed into autumn, the gardener’s thoughts turn to the gratifying display of spring bulbs.

If your garden already includes bulbs that bloom each spring, and you have all you want, relax and let nature do its thing!

If you want more blooms to brighten your spring, however, plant bulbs during the next few weeks.

The general rule is to plant bulbs before the ground freezes, but Monterey Bay area gardeners can only imagine a freeze to schedule bulb planting.

In this temperate climate, bulbs that do not require vernalization (dormant period chilling) are most convenient.

There are many bulbs in this category, including the popular narcissus, plus allium, colchicum, crinum, crocus, gloriosa lily, hyacinth, kaffir lily, muscari, snowflake, spider lily, and watsonia. Most of these are members of the large lily family (Liliaceae), which also includes the tulip.

Several species tulips require little chilling during their dormant period, including Tulipa bakeri ‘Lilac Wonder’, T. clusiana (Lady Tulip), T. saxatilis (Candia Tulip) and T. sylvestris (Florentine Tulip). All these produce demure, colorful blooms.

By contrast, hybridized tulips, with larger blooms and taller stalks, require chilling. Some helpful suppliers offer pre-chilled bulbs of hybridized tulips.

Bulbous plants are native to the globe’s five summer-dry climates, particularly the Mediterranean region, South Africa, and California. Adventuresome gardeners can have a great time growing spring bulbs from one or more of these areas.

Triteleia laxa ‘Queen Fabiola’

Such projects require some research. The larger mail-order bulb suppliers offer at least a few bulbous species from faraway places, among the mainstream varieties, but their catalogs have inconsistent information about the country of origin.

Here are sources of bulbous plant information, by country of origin:

Pacific Bulb Society’s Wiki, a volunteer-written on-line encyclopedia of flowering bulbs, with photographs.
Telos Rare Bulbs, a mail-order nursery in Ferndale (on the California coast, near the state’s northern border), offers a great selection of native plants of California, South America and South Africa.
Mediterranean Area: Alpine Garden Society lists specialized books on bulbous plants, including Bulbs of the Eastern Mediterranean, by botanist Oron Peri. The bulbous plant cognoscenti are thrilled with this newly released book.
South Africa: The Color Encyclopedia of Cape Bulbs (2002), by John C. Manning, Peter Goldblatt, and Dee Snijman.
Chile: Few bulbous plants are native to Chile, including Glory-of-the-Sun (Leucocoryne) and the striking—and rare—Blue Chilean Crocus (Tecophileae cyanocrocus). Both are available from Telos Rare Bulbs. For the short list, visit Chileflora (click on Seeds Shop/Life Form: Bulbous Plants) or Sacred Succulents (click on Rare & Beneficial Plants from Chile), a small, family-run business in Sebastopol, California.
Australia: Gardeners of the land down under cultivate several bulbous plants that originated in other areas, but apparently few if any that are native to Australia. (If you know of any, let me know.) The region’s popular Chocolate Lily (Dichopogon strictus) is attractive, but it’s tuberous, not bulbous.

Screen Shot 2015-11-14 at 12.20.55 PM Through a recent search of the Internet. I found a new book by Attila Kapitany, Australian Native Bulbs (2015). This book highlights eight native
species of bulbs, corms, and tubers, and “discusses many more.” It is available on eBay with shipping costs for the interested buyer to discover.

Cultivating exotic bulbs can be challenging, intriguing and rewarding, as beautiful and out-of-the-ordinary blooms appear in the spring.

***

Comments and Questions are Welcome

Right Time, Right Plants

Posted on October 2, 2015 by tomkarwin

Tom Karwin

Each spring, many gardeners seek new plants for their gardens. That’s understandable, since that is when gardens spring into new life (sorry about that!).

The spring can be a good time to plant seeds for annuals, but the fall is by far the better time to plant perennials because our rainy season, beginning historically around mid-October, hydrates the plants while they establish roots and prepare for the following spring.

For this reason, we have excellent plant sales during the fall, offered by non-profit garden groups that support your gardening success, and of course want to earn money for their activities.

These sales offer California natives and other plants that thrive in the Monterey Bay area’s summer-dry climate and that align very nicely with your plans to build soil health in your garden.

Two early sales happen Saturday, October 3^rd.

The Monterey Chapter of the California Native Plant Society will have its annual plant sale from 10:00 to 1:00 at the Hilton Bialek Habitat at Carmel Middle School. Info: http://montereybay.cnps.org/
Watsonville Wetlands Watch will host its 3^rd annual Pajaro Valley Backyard Habitat Festival and Native Plant Sale from 9:00 to 4:00 at the Fitz Wetlands Educational Recourse Center, at Pajaro Valley High School. Info: http://watsonvillewetlandswatch.org .

Two more sales have been announced for the following Saturday, October 10^th.

The Santa Cruz Chapter of the California Native Plant Society and the UCSC Arboretum will hold their sales together at the UCSC Arboretum’s Eucalyptus Grove. The entrance to the sale is on High Street, is across from Western Drive, on the edge of the UC Santa Cruz campus.

Both sales are open for members from 10:00 – 12:00, and for the public from 12:00 – 4:00. Memberships for both organizations will be available at the gate on the day of the sale.

Info for the CNPS sale: http://www.cruzcnps.org/

Info for the Arboretum sale: http://arboretum.ucsc.edu/ (click on “Events/Recurring Events”)

The Arboretum’s sale includes selections from dry-summer climate regions in California, South Africa and Australia, offering opportunities for venturesome gardeners to add exotic plants to their landscapes. As one example, Melinda Kranj, Curator of the Australian Collections, has shared her knowledge of an iconic Australian plant in “Banksias Breath New Life for a Fall Garden” (click on “News” on the Arboretum website). She wrote, “The UC Santa Cruz Arboretum is currently growing about 50 species, and many different varieties and cultivars” and will have several Banksias available at the sale.

Banksia victoriae

Incidentally, the generic name of this plant honors English botanist Sir Joseph Banks, who collected the first Banksia specimens in 1770, while on Captain James Cook’s first expedition into the south Pacific.

These plant sales are scheduled at the right time, and they offer plants that are right for our regional climate. As always, the gardener should install new plants in the right place in the landscape. Consider mature size and sun exposure, as well as garden aesthetics.

South African Flora

Posted on September 16, 2015 by tomkarwin

As California’s drought stretches into the future, the plants of Earth’s five Mediterranean climate zones attract gardeners’ interest and soon earn their appreciation. Many of these plants are fine additions to the landscape, offering beauty, fragrance and benefits for garden fauna as well as easy cultivation (with some exceptions) and environmental friendliness.

In today’s column, with our feet on the ground, we have an overview of the flora of one of these “summer-dry” zones: South Africa.

This relatively small country’s Mediterranean climate zone is the very small and extraordinary Cape Floristic Region. As background, botanists have identified six Floristic Regions (floral kingdoms) of the world. These are regions with distinctive plant life. The Cape Floristic Region, by far the smallest of the six, is noteworthy for very high diversity of plant life, with over 8,000 species, and very high endemism: nearly 70% of the plant species are native to the Region and nowhere else.

Much of the Region’s botanic diversity grows on the fire-prone shrub land called fynbos, which is roughly comparable to California’s chaparral. Both of these two shrub lands have shrubs with hard leaves, closely spaced on their stems.

The fynbos is the home for numerous small shrubs, evergreen and herbaceous plants, and bulbs, many of which are in three plant families.

The Protea family (Proteaceae), which includes 80 genera and 1,600 species, all in the Southern Hemisphere, and mostly in South Africa and Australia. The family name comes from the name of the Greek god Proteus, who could change between many forms. The adjective “protean” (changeable, versatile) has the same root. Plants in this family have a great diversity of flowers and leaves.

The popular South African genera in the Protea family include

Proteas (sugarbushes), which come in a range of heights, from three feet to nine feet, with unique compound flower heads (correctly, inflorescences) in pink or sometimes red.

Leucospermums (pincushions), most reach four-to-five feet tall, with yellow, orange, pink or red flowers.

Leucadendrons (conebushes), various species grow from three-to-eight feet tall; the striking silver tree (L. argenteum) reaches 25-to-40 feet tall, with “soft, silky, shimmering, silvery-green-gray, lance-shaped foliage.” The cone-shaped flowers typically are surrounded by petal-like bracts, often combining red and yellow colors.

Australia is home to several genera of the Proteaceae, including banksia, grevillea and hakea.

The Cape heaths (Ericaceae) include some 660 species that are endemic to South Africa, and are often called winter (or spring) heather. Another 40 species, including summer (or autumn) heather are native to other parts of Africa the Mediterranean basin and Europe. Most of the Cape heaths are small shrubs, from eight inches to sixty inches in height, with attractive tubular pink flowers throughout the year.

The Cape reeds (Restionaceae). The genus Restio includes 168 species in South Africa. Various species of Restio grow from one-to-ten feet tall, with tiny flowers grouped in spikelets that comprise inflorescences. Other genera in this family of perennial, evergreen rush-like flowering plants are found throughout the Southern Hemisphere.

To view photographs of South African plants, serve the web for the plant’s botanical name and click on the menu option for images. Better yet: to experience the real presence of these plants, browse to arboretum.ucsc.edu, navigate to Visit/Gardens and Collections/South Africa, and tour the Arboretum’s South African collection in person. You could become inspired to bring South Africa’s botanical bounty into your own garden.

The Ageless Aeonium

Posted on August 22, 2015 by tomkarwin

Today, we introduce the genus Aeonium, which includes 35 species, most of which are from the Canary Islands, northeast of Africa.

These plants are characterized by the development of rosettes of leaves on basal stems, i.e., stems that rise from the plant’s roots.

The generic name, Aeonium, comes from an ancient Greek word that means “ageless.” In fact, for most species, the rosettes die after producing a flower, although the entire plant lives. A few species are monocarpic, meaning that they produce a single rosette without a stem, and then the entire plant dies.

Popular Cultivars

A. ‘Zwartcop’ (Black Rose), a cultivar of A. arboretum, develops rosettes with very dark reddish-purple, almost black leaves, on stems that can rise to four feet. This plant produces effective displays in the landscape or in a mixed container, especially when contrasted with yellow flowers like those of the plant’s own blossoms.
A. ‘Sunburst’ (Copper Pinwheel), a cultivar of A. davidbramwellii, is a variegated form, with large rosettes with variegated green and white leaves edged in bright, coppery red. The stalks rise up to 18 inches. ‘Sunburst’, like other variegated plants, can provide pleasing contrast in the garden.

3. A. nobile (Noble Aeonium) produces a single, stemless rosette up to nearly two feet in diameter, making it entirely distinctive among the aeoniums. The leaves are yellowish, with a reddish edge when grown in bright light. This is one of the monocarpic aeoniums: it dies after producing its reddish blossoms.
A. tabuliforme (Saucer Plant, Dinner Plate Plant) is another monocarpic aeonium that provides a single, unique, nearly flat stemless rosette.

Cultivation

Aeoniums will be dormant during the summer months and resume growing in the early autumn.

They are very easy to grow in containers, where they flourish with their shallow roots and occasional watering. Use a normal potting soil, rather than a fast-draining cactus mix. In the Monterey Bay area, they prefer bright morning sun and afternoon shade. Fertilize only when the leaves become yellowish, indicating nitrogen deficiency. Too much fertilizer will promote too-rapid growth and weak stems.

When grown in the garden in this area, aeoniums require little care. As with container plants, avoid very rich soil and fertilizers.

Propagation

All aeonium species and hybrids can be propagated from seeds, but most are propagated easily from stem cuttings. This might be done to produce additional plants or to bring a rangy plant into a more compact form. During the plant’s normal growth period, from autumn to mid-spring, cut a rosette with up to five inches of stem (shorter for smaller, shrub-like forms) and place in a cool shady place for at least three days, to heal over. Then, place the cutting in a normal potting mix, in a small container, and in a shaded, windless location to reduce moisture loss. After the plant has established roots, place in a container or in the garden.

The monocarpic species are not propagated from stem cuttings, but from leaf cuttings, which are more successful with A. tabuliforme than with A. nobilis.

Aeoniums are drought-tolerant plants that are easy to cultivate and interesting additions to the garden.

Restoring Soil

Posted on July 12, 2015 by tomkarwin

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.


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.

Bare Root Trees and Shrubs

Posted on February 15, 2015 by tomkarwin

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.

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!

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