What is Blooming Now

Posted on December 29, 2012 by tomkarwin

If today’s walk through your garden yields satisfaction, congratulations!

If it tilts toward disappointment, a good time for seasonal planting would be now.

Many plants need a dormant period to prepare for the spring, but many other plants will bloom while most are dormant. We can’t turn winter into spring, but with a bit of planning we can enjoy color in the garden at any time of the year.

The moderate climate of the Monterey Bay area supports year-round color possibilities that are elusive or non-existent in many other areas.

Here are examples from my garden.

Salvias originate from several parts of the world, and some species from Mexico are in bloom now.

S. wagneriana (Wagner Sage) stands as one of my favorite blossoms, with pink corolla and white calyx. This large shrub does best in partial shade, and tends to sprawl in full shade.

S. karwinskii (Karwinski’s Sage), another large plant, displays pink-coral and green blooms from fall to spring.

S. holwayi (Holway’s Sage), our third example, grows only about three feet high, but spreads to cover an increasingly large area. Its small blooms are red and purple, and prolific.

Aloe arborescens (Torch Aloe) produces numerous vibrant red-orange inflorescences (called racemes) about eight-to-ten inches long. The plant grows easily and can rise to nine feet tall. In South Africa, where it is endemic, it is called called Krantz Aloe. The Afrikaner word ‘krantz’ means a “rocky ridge” or “cliff,” indicating its natural habitat, but it thrives in deep fertile soil.

Helleborus argutifolius (Corsican Hellebore) comes from the Mediterranean islands of Corsica and Sardinia. It grows in sun or shade and produces many seedlings that germinate readily. (I have many plants in a growing swath.) It grows to four feet tall and wide, and produces many pale green flowers from late December to March. After flowering, it can be cut to the ground to stimulate a new cycle of growth.

Daphne odora “Aureo-marginata” (Winter Daphne), which comes from China and Japan, is appreciated for its evergreen, gold-edged foliage, and prized for its beautiful rosy-pink flower buds that open to white, sweetly fragrant flowers in winter and early spring. The flowers grow on the stems, so they are not useful in arrangements, but can be brought indoors to float in water.

Edgeworthia chrysantha (Chinese Paper Bush) is a relative of the Daphne odora (both from the family Thymelaeaceae) and another sweetly fragrant winter bloomer. To be quite honest, both the Daphne and the Edgeworthia in my garden are in bud at the moment, but they will be in flower in January through March.

It is always a pleasure to have flowers in winter. Still, many conifers and succulents provide foliage with much visual appeal.

Enjoy your winter garden.

Several garden writers have listed plants that bloom in each season of the year. One of the better books is The Perennial Garden: Color Harmonies through the Seasons, by Jeff Cox and Marilyn Cox (Rodale Books, 1992).

A book that I refer to often for various purposes is The California Gardener’s Book of Lists, by Catherine Yronwode, with Eileen Smith (Taylor Publishing, 1998). Among its other treasures are lists of “Perennials that Bloom in Winter” and “Shrubs That Provide Winter Interest.”

Gifts for Gardeners

Posted on December 1, 2012 by tomkarwin

This is the season to make your favorite gardener happy.

We will explore gifts for a gardener in these four categories: Upscale, Kitsch, Junktique, and Living.

Upscale depends on what the recipient would find enduring in appeal and impressiveness. This is not the same as “expensive,” but alas upscale items tend to be costly.

The Kitsch category is often defined with negative terms, e.g., tasteless, aesthetically deficient, and excessively sentimental. Never mind! One person’s “kitsch” is another’s “cute.” This is hazardous territory for the gift-giver, unless his or her taste reflects that of the recipient.

Items that may be considered Junktique are often old, but the essential concept is that they are recycled: their use is the garden is not the same as their original purpose. (A friend collects antique gardening and farming tools, but those belong in a category of their own.) This is where you find a discarded bed frame with a new life as a “garden bed.”

Finally, we have the Living category, the principal members of which are plants and personal services. This category might also include certain fauna (a nice koi for a friend’s pond, for example) but does not include feral mammals or herbivorous insects. That would be whimsy gone overboard.

Watch for next week’s column for an exploration of the Kitsch, Junktique and Living categories. For today, here are examples of the Upscale category. (I have no financial interest in any of these items, but am available for field-testing!)

Bronze garden tools are stunning in appearance, quite durable in use, and suggestive of the Bronze Age (late to arrive in the Americas). Find them at www.implementations.co.uk.
Hand-made, heirloom-quality garden tools are American made and exceptionally rugged. One source is www.fisherblacksmithing.com.
How about a high-grade shovel, engraved with the gardener’s name? Find it at the Best @ Dianne B: www.diannebbest.com/shovel.php.
Nicely designed, and well-made garden pots, statues or decorative art pieces will be welcomed, especially if they echo the style of the recipient’s garden. A Gothic urn wouldn’t belong in a contemporary garden, for example, unless one could call it eclectic. Many choices are available at www.haddonstone.com (click on “Garden Ornaments”).
Decorative corners for raised beds, available from www.outdooressentialproducts.com, combine an attractive appearance with a necessary function. A gift set of four corners could be complemented with the lumber for a sizable raised bed, a desirable asset in most gardens.

The Upscale items listed above can be ordered online; early decision-making would provide time for timely delivery.

In all cases, evaluate a gift you are considering by asking if you would be an appreciative recipient. That works best when you are a gardener yourself!

This essay lists the website of the British maker of bronze garden tools, but these tools are in fact available closer to home. Harley Farms Goat Dairy, in Pescadero, California, contacted us to report that they can supply the full range of these tools, “along with goat cheese and other high quality hand made products.” In fact, I saw these impressive tools at the Harley Farms booth at the 2012 San Francisco Garden Fair, but then misplaced their contact information! The website has photos of the tools.

Growing Terrestrial Orchids

Posted on November 17, 2012 by tomkarwin

Most orchids are epiphytes, meaning that they grow on another plant. Epiphytes are not parasites, which are plants that scrounge nutrients from another plant. An epiphyte attaches itself to another plant (a tree, usually) and gets moisture and nutrients from the air and rain and sometimes from debris accumulating around it.

To grow an epiphytic orchid, the gardener must reproduce the temperature, humidity and light level that the plant has evolved to require. This is true for all plants, to be sure, but these orchids have become accustomed to very particular environment that can be difficult for the gardener to provide.

Experienced orchid growers claim that success with epiphytic orchids requires only creating the plant’s preferred conditions. This typically includes planting the plant in coarse bark chips to provide ample access to air.

Without denying the accomplishments of amateur orchid growers, I confess to having killed more than my share of epiphytic orchids.

Given that sad history, I am delighted to have discovered hardy terrestrial orchids. These are plants that thrive in well-drained soil and within a moderate climate like that of the Monterey Bay area. Some terrestrial orchids will even take freezing temperatures.

Terrestrial orchids that are popular for home gardens have been described in three groups according to water needs:

Upland species include Lady’s Slipper (Cypripedium), Chinese Ground Orchid or Hyacinth Orchid (Bletilla) and Hardy Calanthe (Calanthe);
Transitional species include Grass Pink (Calopogon), Marsh or Spotted Orchid (Dactylorhiza), Egret Flower (Habenaria), Fringed Orchid (Platanthera), Fragrant Ladies’ Tresses (Spiranthes), and Helleborine (Epipactis);
Wetland species include Rose Pogonia (Pogonia).

Three years ago, I acquired a small Lavender Chinese Orchid (Bletilla striata), which is widely available, and planted it in semi-shade, assuming that all orchids want shade. Although I never watered or fertilized the plant, it grew well but produced only occasional blossoms. This was disappointing because Bletillas often will have as many as 20 flowers on a single spike.

Then I learned that this plant prefers full sun exposure. I lifted it and discovered it had developed about twenty pseudobulbs, which are storage organs (like tubers) that some orchids produce. These can be planted six inches apart, about three inches deep, so I should have several patches of these plants in bloom in the spring.

Terrestrial orchids can provide an exotic display in the garden without requiring extraordinary care. The Chinese Ground Orchid is particularly easy to grow, and the Lady’s Slipper and Hardy Calanthe are also good choices for most gardens. The Transitional and Wetland species require more moisture, making them inconsistent with water conservation goals, but a small display would be tolerable.

If you enjoy the unique beauty of orchids, but have had poor experiences with epiphytic species, growing terrestrial orchids could be an appealing option.

Here are current books about the cultivation of hardy orchids.My principal reference for this column was the Mathis book, but other books listed offer additional information and other perspectives.

The Orchid Manual: For the Cultivation of Stove, Greenhouse, and Hardy Orchids, With a Calendar of Monthly Operations, and Classified Lists of Species, by Thomas Appleby. Forgotten Books (June 23, 2012) (Note: this is a reprint of a classic book published in 1845.
Growing Hardy Orchids, by Philip Seaton, Phillip Cribb, Margaret Ramsay and John Haggar. Royal Botanic Gardens, Kew; Original edition (March 15, 2012)
Growing Hardy Orchids, by John Tullock. Timber Press (September 15, 2005)
The Gardener’s Guide to Growing Hardy Perennial Orchids, by William D. Mathis. The Wild Orchid Company (2005)
Hardy Orchids, by Phillip Cribb and Christopher Bailes. American Orchid Society (December 1989)
Hardy Terrestrial Orchids for Perennial Gardens with a focus on Bletilla, Calanthe, and Spiranthes – Excluding Cypripedium, by Dennis Carey & Tony Avent. Plant Delights Nursery Inc.

Selected sources of hardy terrestrial orchids:

Wild Orchid Company, Carversville, Pennsylvania
Poplar Hills Nursery, Alexandria, Virginia
Fraser’s Thimble Farms, Salt Spring Island, British Columbia, Canada
Brent and Becky’s Bulbs, Gloucester, Virginia

Small Gardening

Posted on November 10, 2012 by tomkarwin

The gardening world has been buzzing about small gardens. The current interest in this topic might reflect a trend toward small-scale properties or 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)

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

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, African bulbs, aquatic plants) or any other theme of interest. A theme provides coherence to the garden and a rational 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.

Here is a link to an article with additional thoughts about small gardening: “Big Help for Small Gardens.”

Coming to Grips with Thrips

Posted on September 29, 2012 by tomkarwin

Happily, several years have passed since I’ve noticed thrips in my garden, but they are back!

Thrips are flying insects that are less than 1/20 of an inch long and eager to suck juices from plants. There are over 500 genera and 5,000 species of thrips, some of which are beneficial predators of mites, scales and even other thrips. Others feed on fungal spores or pollen, and some feed only on favored plants, such as avocados, citrus, blueberries, or various others.

My garden’s visitors almost certainly are Western Garden Thrips (Franklinia occidentalis), which attack a wide range of herbaceous ornamentals, vegetables, fruits and some shrubs and trees, including roses and stone fruits.

Thrips are poor flyers but can find juicy plants and infest all of a large shrub or a good-sized bed of a plant that they find tasty.

In my garden, they found a 200 sq. ft. bed of Bergenias (an unidentified cultivar of the popular species, Bergenia crassifolia). This plant from central Asia has numerous common names: Elephant Ears, Pig Squeak, Large Rockfoil, etc. It is an attractive groundcover plant, growing one-to-two feet high, with clusters of small, bell-shaped pink flowers on stems that rise above the foliage in early spring.

Bergenias are generally free of pests, at least until thrips discover them.

Thrips might make only limited damage to ornamental plants and could be ignored. When conditions are favorable, however, they can cause great cosmetic damage.

When thrips attacked my Bergenia bed, nearly all the leaves, each about four by six inches, became discolored and distorted, and their upper surfaces turned silvery gray, the result of losing their waxy surface. The leaves also were stippled with black specks of the thrips’ fecal matter.

The normal growth of Bergenias has new leaves emerging above older leaves that turn brown without dropping off. New leaves cover the old leaves, but removing the dead leaves improves the plant’s appearance. In this instance, the action of the thrips revealed the dead leaves, and the entire bed was devastated.

The damage was limited to the leaves. The stems and roots of the plants were alive and well, and able to produce new leaves. Our treatment was to remove all living and dead leaves, using garden clippers, and then spray the plants with Spinosad, an organic pesticide that kills insects both by direct contact and by ingestion.

I used a Spinosad-based product, Captain Jack’s Deadbug Brew, in a container designed conveniently as a hose-end sprayer. Despite its promising name, the spray doesn’t guarantee success: a follow-up spray might be needed to control the newest of up to eight generations of thrips for the year.

Thrips are members of the order Thysanoptera. The earliest fossils of thrips date to the Permian Period, 250 to 299 million years ago. This period was the last part of the Paleozoic Era, which ended with the largest mass extinction in Earth’s history, when nearly 90% of marine species and 70% of terrestrial species died out.

That thrips were among the survivors of that period suggests the difficulty of eliminating them from our gardens.

When the gardener suspects that thrips are present, they can be detected either by close examination of the underside of affected leaves, or by beating or shaking a branch or flower onto a sheet of paper. Yellow sticky traps also can be used to monitor their presence.

The most important way to encourage biological control of pest thrips is to conserve naturally occurring populations of beneficial insects, e.g., predatory thrips, minute pirate bugs, predaceous mites, and green lacewings . This can be done by controlling dust and avoiding the use of persistent pesticides in the garden.

For other control, see the University of California’s Integrated Pest Management information page on How to Manage Pests—Thrips.

Growing Gorgeous Geophytes

Posted on September 15, 2012 by tomkarwin

The fall season invites gardeners to plant bulbs to blossom in the spring and create bright swaths of color for the new gardening year.

Right now is an excellent time to design bulb bed(s) and select spring bulbs for the garden. There is a lot to consider.

One strategy is to favor the most familiar bulbs, choosing either old favorites or recent introductions. The most popular bulbs include Daffodils (Narcissus), Tulips (Tulipa), Hyacinths (Hyacinthus) and Dutch Crocuses (Crocus vernus). Garden centers offer many varieties of these plants: the long popularity of daffodils and tulips in particular has motivated hybridizers to develop a range of colors and interesting forms.

The next most familiar bulbous plants include Lilies of the Valley (Convallaria, from rhizomes), Spanish Bluebells (Scillas), Grecian Windflowers (Anemones, from tubers), Snowdrops (Galanthus), Dwarf Irises (Iris reticulata, from bulbs), and Grape Hyacinths (Muscari). There are many appealing options within these genera, as well.

Adventuresome gardeners can explore a long list of less familiar bulbs, each of which brings unique characteristics. Visit my website, ongardening.com, for links to additional options.

A different group of geophytes are summer-bloomers. This group includes Gladioli, Calla Lilies, Dahlias, Tuberous Begonias, and Crocosmias. They are planted in the early spring about the same time we plant tomato seedlings.

Other geophytes we enjoy are fall-bloomers, which are planted in the late summer: Autumn Crocus, Winter Daffodil, Guernsey Lily, Saffron Crocus, and some species of Snowdrops.

With planning, you could enjoy glamorous geophytes during much of the gardening year.

Some spring-blooming bulbs need a chilling period to bloom their best. Winter in the Monterey Bay area rarely provides a chill that is long enough and cold enough for these plants, so schedule six weeks of cold storage. The kitchen refrigerator will suffice except for larger projects, when gardeners will appreciate the luxury of a second refrigerator. Consider organizing a chilling co-op with gardening friends.

Many mail order bulb sellers offer pre-chilled bulbs to be shipped at the right time for local planting. A welcome service!

Here are the basics of planting bulbs. Choose a site that receives all-day sun, and drains well. Select larger bulbs of the preferred genus. Plant the bulbs at a depth that is about three times the bulb’s diameter, and take care to position them with the pointed end up.

Bulbs can be planted very close together and may be arranged in either formal or informal patterns. Fertilizers are not required, but a small amount of bone meal in the planting hole could help. For clay soil, add compost to improve drainage. Water to settle the soil then let the seasonal rains take over.

Prepare now for a spectacular spring.

More.

Information About Uncommon Geophytes

North Carolina State University

The Plant Expert

Pacific Bulb Society Wiki

Mail-order Suppliers of Uncommon Geophytes

Brent and Beck’s Bulbs