Help to Avoid Monarch Extinction

Recent news reports have described a dramatic decrease in California’s population of Western Monarch butterflies. Thirty years ago, over 4.5 million of these beautiful flying insects migrated annually from Mexico to overwinter on the Pacific Coast, with huge, fascinating clusters at famous sites, including Pacific Grove and Natural Bridges State Beach. Their numbers have declined over the years: this year the count was under 30,000 individuals, 0.6% of the population’s historic size. Researchers had established 30,000 as the “quasi extinction threshold,” so coming under this threshold suggests that this species (Danaus plexippus plexippus) is approaching extinction.

Another, larger number of monarchs migrate from Mexico to the northern plains of the United States, so extinction is not imminent, but that population also has been shrinking in recent decades.

The causes of the decline in the monarch population begin with the loss of suitable habitat, defined as areas that include both milkweeds (Asclepias sp.) that Monarch caterpillars depend upon, and pollen plants that provide nutrition for the adults. Milkweed plants are too often deleted from the environment by agricultural pesticides, particularly glysophate (RoundUp), which is used to kill unwanted plants among commercial crops.

Other factors include pesticide use, climate change, and logging and development projects that degrade overwintering sites.

Gardeners can help rescue monarch butterflies back from the threat of extinction by growing milkweed plants in their gardens, with preference for locally native species of this plant. Fifteen species of milkweed are native to California. Nearby sources of seeds for native species include Pacific Coast Seed, in Livermore; Seedhunt, in Freedom; and S&S Seeds, in Carpenteria. For information on growing milkweed, download “Native Milkweed in California: Planting and Establishment.”

A related project for gardeners is to include pollen plants for the adult monarch butterflies. Useful advice for such a project is available in “California Coast: Monarch Nectar Plants,” available here.

Both of these publications are free downloads from the Xerces Society for Invertebrate Conservation.

Monarch butterfly on Milkweed pod. Photo by Edward K. Boggess, U.S. Fish & Wildlife Service Posted on Wikimedia Commons

The Xerces Society has also produced a five-step call to action for recovering the western monarch population. This plan emphasizes protection of overwintering and breeding habitats, protection from pesticides, and continuing research on western monarch recovery. In addition to actions in their own gardens, people concerned with threats to the monarch population could support large-scale initiatives that respond to the Society’s call to action.

Protecting the Western Monarch Butterfly from extinction has at least three broad objectives. One is for us all to enjoy the phenomenon of these beautiful creatures flitting about in our gardens. A second objective, oriented to the ecosystem, is to maintain these butterflies as food sources for birds, which we also appreciate and enjoy. Thirdly, Karen Oberhauser, director of The Monarch Butterfly Lab at the University of Minneapolis, advises that monarch butterflies are valuable subjects for ongoing studies of migration, species interaction, insect population dynamics, and insect reproduction.

We can strive to keep monarch butterflies in our environment, but we should also acknowledge the larger picture of the extinction of species. Before humans spread across the globe, species extinctions occurred for various reasons at a very slow rate. Human activity has increased the average rate of extinction by somewhere between 100 to 1,000 times the previous historical rate., and is accelerating

Today, according to Edward O. Wilson, distinguished American biologist, the science community estimates that Planet Earth has about 10 million living species, one of which is human people (Homo sapiens). About 20 percent of these species are known, and 80 percent are undiscovered. If the extinction of species by human activity continues to accelerate, E.O. Wilson says, we could eliminate more than half of all species by the end of this century.

We can slow this trend a little by working as individuals. Consider adding California native milkweed and pollen plants to your garden this year, to sustain the monarch butterflies.

Build Your Rose-pruning Proficiency

The Monterey Bay Rose Society will hold a series of rose pruning workshops again this year. This group of dedicated and community-spirited rosarians offers to share its expertise, so that gardeners who also appreciate the Queen of Flowers will enjoy fine blossoms during the coming season.

Species roses grow nicely with little or no care by gardeners. We occasionally read stories about “rose rustlers,” who are rose lovers who are fascinated by early rose varieties that have been lost to cultivation, and find them still growing unattended in cemeteries.

In California, for example, these historic varieties could date back to Gold Rush days. For a sampling of Sacramento’s “cemetery roses”, visit the website created by eminent garden photographer Saxon Holt,

Modern roses, particularly the popular hybrid tea roses, grow best with regular care and feeding. We prune modern roses to stimulate new growth, support good health, and promote desirable form. Well established roses respond quite well to dormant season pruning: they come back vigorously after even heavy pruning.

If you have roses in your garden and lack confidence in your pruning talents, resolve to build and apply those skills this year. We are now within the rose’s dormant period, so the next few weeks is good time to schedule such a project.

There are various ways to learn about rose pruning. When I need to learn about some aspect of gardening, I generally open relevant books in my collection or the library, or search the Internet’s vast resources on gardening techniques. To learn about pruning roses, a good place to look online is the website of the American Rose Society.

Another strategy involves searching the Internet for “pruning roses” or a similar phrase. It’s also OK to use a natural language search, e.g., “how should I prune my rose bush?”

When your search yields multiple “hits,” you can visit selected sites to find a tutorial that emboldens you to venture into your rose garden with clippers in hand.

Some gardeners will learn best from a video demonstration. If that is your preference, direct your search results by clicking on “video” at the top of the computer screen. With today’s technology, it is easy to record a video demonstration and distribute it via the Interest. It is not easy, however, to produce a video recording that communicates effectively, so you might benefit by viewing several short video clips. This can be done in one sitting, and reveal both different presentations of basic technique and variations in the methods of different gardeners.

Although much can be learned about rose pruning from printed and digital resources, the opportunity to learn directly from a friendly expert will be ideal for many gardeners, especially when the expert hands you the clippers and talks you through the process. The rosarians of the Monterey Bay Rose Society will offer the following free pruning workshops in the near future.

  • January 26, 10:00 am, San Lorenzo Nursery & Garden Center, 235 River St., Santa Cruz, CA 95060
  • January 27, 10:00 am, Mission San Antonio de Padua, Annual Cutting of the Roses, Jolon, CA. For driving directions, click here.
  • February 2, 10:00 am, Bokay Nursery, 30 Hitchcock Rd, Salinas, CA
  • February 23, 10:00 am, Alladin Nursery & Gift Shop, 2905 Freedom Blvd, Watsonville, CA 95076
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For more information on the Society, visit its website.

Prune your roses during this dormant season, and expect healthy plants and great blooms in the spring.

Glorious Geophytes for the Garden

Right now is a good time of the year to plant spring-flowering bulbs. There are many available varieties for venturesome gardeners to consider, and we regularly recommend trying unfamiliar botanical treasures. Today’s column features daffodils, which could well be the most popular and most frequently hybridized of the geophytes.

‘King Alfred’ Daffodils

Here are reasons for including daffodils in your garden.

Really Beautiful

Many flowers are delightful in the garden, and many gardeners have their favorites, but just about everyone enjoys daffodils, especially when they declare the arrival of the spring season. Daffodils have graceful stems, attractive foliage, and unique blossoms. Trumpet daffodils, the most familiar division within the genus Narcissus, have blossoms that feature the trumpet-shaped corona surrounded by six petal-like tepals, which form the perianth. The corona and perianth might have the same color, or different colors.

Numerous Hybrids

A very large and growing number of hybrid daffodils are available through garden centers and mail order nurseries. Many plants are yellow or white, or combinations of those colors; hybridizers have introduced cultivars with green, pink, orange and red elements. There are interesting and pleasing color combinations for various tastes.

The growing number of hybrids includes variations of shapes, particularly in the coronas that might be single or double in form, or might have ruffled or frilly edges.

There are also varieties that bloom in at various rtimes, as early a late December and as late as early, mid- or late spring, so with a little planning you can create an extended display.

Perennialize Themselves

During their growing season, many hybrid daffodil bulbs form side bulbils that develop new bulbs and provide more flowers in the following season. A clump of daffodils will increase in sixe from one season to the next. In time, the clump can be come crowded, and the gardener can dig up the bulbs for replanting over a larger area, or gift them to friends.

Naturalize Themselves

Some varieties will develop seeds and sow them naturally to form additional populations of plants Over a few seasons, they can spread throughout a meadow area, providing a stunning display.

Free of Pests and Diseases

The bulbs and foliage of daffodils are poisonous to most pests, because all parts of the plant includes the toxic chemical, lycorine. Consequently, the plants have minimal problem with deer, gophers or other rodents. If such pests tend to favor your garden, daffodils will provide a fine display without the expectation that plants will disappear when you’re not looking.

Daffodils are not immune to diseases, and basal rot and fungi could attack the plants, as will as nematodes, bulb flies, or viruses. However, plants grown in good soil with good drainage, and regular care generally will resist such difficulties. The references listed below include helpful information about managing such problems.

Easy to Plant

Daffodil bulbs are planted three times the width of the bulb apart, three times the width of the bulb deep. They can be planted singly, with a trowel or other tool, or in groups by removing the desired amount of soil from the planting area, positioning the bulbs, then replacing the soil. Each gardener has a favorite planting method. In any case, planting a large number of daffodil bulbs can be accomplished quickly.

For more information, here are recommendations of Becky Fox Matthews a past president of the American Daffodil Society:

The American Daffodil Society – The ADS is :The AmericanCenter for Daffodil Information” providing rich resources on its website.

Daffseek – A online photo database with an incredible amount of features (different languages, photos from all over the world, daffodil genealogy and more), made free to the public by the American Daffodil Society;

Daffnet – A discussion forum for For people interested in growing, showing, or hybridizing daffodils

Dafflibrary – Books, articles and journal about daffodils

Dafftube – Slide presentations and video recordings, many of which were presented originally during national or regional meetings of the American Daffodil Society.

Many thanks to Becky Fox Matthews for sharing these links.

Another useful source of information is the website of England’s The Daffodil Society. The Society was established in 1898 as the specialist society of Great Britain for all who are interested in the Genus Narcissus

 Daffodil bulbs will be available now, and through most of the fall months from local garden centers and several mail order nurseries. Several mail order nurseries throughout the United States will offer daffodil bulbs. An Internet search for “daffodil bulbs” will list several sources.

Many gardeners will favor west coast suppliers on the premise that they grow their bulbs under conditions like those of the local area.

In addition, I will list Brent and Becky’s Bulbs, located in Gloucester, VA, not the west coast. This family business began in the early 1900s as a daffodil specialist and has since grown to offer over 1,000 varieties of bulbs. Daffodils continue to be their favorite product, and they offer many beautiful cultivars. Their website also offers solid advice on cultivation. Click on the menu for “Media.”

If you don’t already have daffodils in your garden, this is the time to select and order cultivars that speak to you, and plant the bulbs in preparation for a delightful display in the spring.

Strategic Use of Specimen Plants

Recently, we focused on three basic priorities for landscaping: develop a short list of plants, install significant numbers of each kind of plant, and select some unfamiliar plants that will fit into your plan.

A complementary strategy emphasizes the strategic use of specimen plants, which are “unusual or impressive plants grown as a focus of interest in a garden.” A specimen can thought of as an example of a category, but

A plant could function as a specimen plant if it is sufficiently large, especially showy, striking in form, or quite unusual. Note that a plant doesn’t qualify as a specimen plant simply by being an isolated instance of some plant. In other words, a garden of single examples of various plants does not work as a landscape of specimen plants. 

Conversely, a plant that works as a specimen because it is large, showy, striking or unusual probably would not work as a component of a mass planting. Instead, a specimen plant complements a mass planting.

Many plants could qualify as a specimen plant. Garden designers often will choose a tree of appropriate size as a specimen plant. Japanese maples, for example, are popular selections for this purpose.

The placement of a specimen plant contributes significantly to its effectiveness. In many cases, the specimen will succeed best as a contrast to a fairly large grouping of plants, especially foliage plants, e.g., hedges.

A “large, showy, striking or unusual” plant that is apart from other plants also could function as a specimen plant.

As an example from my garden, we have a Kennedia beckxiana ‘Flamboyant’, which is an evergreen climber in the Pea Family (Fabaceae), and one of the UCSC Arboretum’s Koala Blooms Australian Plant Introductions. The plant’s common name, Cape Arid Climber, refers to a region in western Australian.

Kennedia becksiana ‘Flamboyant’ climbing on a stairway

The plant’s generic name honors a British nurseryman, John Kennedy, and its specific name honors Gustav Beckx, a 19th century Belgian consulate General in Australia.

It earns the variety name ‘Flamboyant’ with its 2-inch long orange-red flowers with a showy large lime-green central spot at the base of the reflexed keel petal.

Kennedia beckxiana blossom (Wikimedia photo by Christer Johannson via Creative Commons)

I acquired a five-gallon plant about a year ago from the Arboretum, and installed it to climb on a stairway. It has grown vigorously there, and will soon reach its mature height of ten feet.

My online research into the cultivation of this robust plant suggests that it should be cut back heavily after flowering to prevent invasive growth.

Given its prominent location and showing blossoms, my Cape Arid Climber will hold its own as a botanical focal point.

Look for a spot in your garden where a specimen plant could attract the eye and add interest to your landscape. You might have a fine selection already in place, or one that could be moved to such a special location. If you have “spotted the spot” but don’t have a specimen plant in hand, you can anticipate the pleasure of choosing one for your garden.

Mark Your Calendar

The Monterey Bay Area Cactus & Succulent Society will hold its Fall Show & Sale on September 29th and 30th, in nearby San Juan Bautista, where there is enough space for Society members to fill some eighty tables with fascinating plants for sale or display. We’ll have full details about this event in next week’s Home & Garden section, so be sure to schedule the date for this opportunity to acquire succulent plants for your landscape.

Landscaping Priorities

This year’s Fall Equinox lands on September 22, marking the unofficial start of the planting season.

Installing new plants in your garden during the fall provides them time to establish roots and prepare for leafing out and blooming in the spring. Ideally, we would have our historic pattern of winter rains during this time, so that the plants will have ample moisture to work with.

An additional benefit of this planting schedule might include end-of-season plant clearance sales at your favored garden center or nursery. You can feel like a savvy garden shopper when you acquire plants at good prices in the fall, and resist the temptation to stock up in the spring, when small plants have been forced into seductive blooms with nitrogen fertilizers.

The planting season is still a couple weeks away, so right now is a good time for planning to select and install plants in your garden. Having a plan when you open a mail order catalog or walk into a garden center will prepare you to focus your targets and avoid becoming overwhelmed by the array of possibilities.

Strategies for garden planning in the Monterey Bay area include emphasizing drought-tolerant plants, or California native plants, or a particular theme of your own choosing. Earlier versions of this column have addressed such strategies.

Today’s column describes additional strategies suggested by Rochelle Greayer, author of Cultivating Garden Style (Timber Press, 2014). In her online newsletter, Pith + Vigor, Greayer recently identified three mistakes that gardeners make when designing with plants:

  • Too many different plants
  • Not enough plants
  • Planting just the plans you know.

Let’s consider positive strategies in these three areas.

First, develop your landscape around a just nine to twelve different plants. Selecting plants in this short list for specific roles will bring order and cohesion to the landscape, and avoid the chaos that too often results from impulsive additions of individual plants.

Second, once you have selected your short list of plants, install lots of them. This strategy is related to adding plants in clusters of three, five, or any other odd-numbered quantity, to present them in a natural and pleasing manner. As you reach larger numbers, install the plants in swathes or bands to provide a landscaping effect. Greayer says, “Repetition gives a scheme flow and rhythm. Repetition is a savvy designer’s best trick.” For example, I recently planted two parallel arcs of blue and yellow irises as a color statement for next spring. Over the next few seasons, these plants will increase to provide increasingly dramatic displays.

A swath of Dalmation Iris (Iris pallida ‘Variegata’) backed up with Lavender plants
A bed of hardy geraniums (Geranium × cantabrigiense ‘Biokovo’ ) with a garden art pheasant

Related to the idea of repetition planting is the installation of plants with close spacing. While you might be tempted to spread plants out to cover space in the garden, having open areas between plants reduces their visual impact and invites the growth of weeds. Close spacing reflects the natural tendency of plants to propagate and develop into colonies. It also functions as “green mulch,” denying weeds the sunlight they need to develop.

Third, explore the wonderful world of plants to find good choices for your short list of selections for the landscape. It’s always important to select plants that are suitable for the climate, soil and exposure of the locations for which you are planning, but there are always many interesting selections that are both suitable for your garden and new to your experience. Relying on common and familiar plants will doom your landscape to being (gasp!) ordinary. Discover interesting plants that will bring excitement to your garden, and invest time in learning how to cultivate them successfully.

In review, there are three strategies for planning the development of your garden during this planting season: develop a short list of plants, install significant numbers of each kind of plant, and select some unfamiliar plants that will fit into your plan and provide a fresh new look to your landscape.

Enjoy this fall’s planting season, and your garden’s coming spring!

Dividing Perennial Plants

As the blooms fade on your perennial plants, the opportunity arrives to propagate your favored specimens by through root division.

The best candidates for this process will have been growing for at least two years, and preferably a bit longer. The ideal time for propagation by root division is after a healthy plant has had time to develop a substantial root system, and before it has become crowded and less productive of blossoms. When divisions are planted, they should be watered lightly and shaded temporarily to limit loss of moisture.

The preferred time of the year to divide perennials is early spring or early fall, rather than the mid-spring to late summer period, when perennial plants are growing and producing blossoms. With this schedule in mind, right now is a good time to consider which plants to divide. This timing gives the divided plants the fall and winter months to develop roots and prepare to burst into bloom next spring.

The general guidelines mentioned above apply to all kinds of perennial plants, but the process differs somewhat with broad categories of these plants.

Rhizomatous and Tuberous Plants

Plants that grow from rhizomes or tubers can be dug up carefully with a garden fork, separating the rhizomes or tubers by hand or knife, and replanted at the same depth as the original plant. Tuberous plants include Arum, Calla (Zantedeschia), Canna, Dahlia, Spurge, and others.

Examples of rhizomatous plants are Iris, Canna and Bergenia. Other in this category: ginger (Zingiber officinale), the related White Ginger Lily (Hedychium coronarium), and the bamboos, which are members of the grass family (Poaceae) and manage propagation quite well on their own.

Blossom of White Ginger Lily
Rhizome of White Ginger Lily

Once dug and divided, these plants could be replanted immediately, or should be kept in a cool and dark place until a convenient time for replanting in the fall.

Clumpers

Another category of perennial plants is the “clumpers,” which have fibrous root systems and clumping growth habits. These plants’ root balls can be dug up with a garden fork or spade, and then either pried apart by hand or split with the spade. The gardener might need to use two garden forks to divide really large root balls.

The number of divisions to be made from a given plant will depend upon the size of the root ball. Often, dividing the root ball into four quarters will be appropriate. While a larger number of smaller divisions might be desirable, they could require more time to become ready to bloom.

The roots of divided plants in this category should not be allowed to dry out. Ideally, they should be dug during an overcast day, replanted promptly, and watered in. Trimming the foliage to reduce transpiration also will help the plant to bounce back from the process.

The clumpers comprise a large group of perennial plants. Examples: coral bells (Heuchera), cranesbills (Geranmium), columbines (Aquilegia), daylilies (Hemerocallis), plantain lily (Hosta), primroses (Primulus), lamb’s ears (Stachys), bugleweeds (Ajuga), Japanese anemone (Anemone hupehensis, which propagates readily on its own), stonecrop (Sedum), yarrow (Achillea), and several larger grasses.

Runners

These plants have shallow stolons or thin rhizomes, and spread across the ground. They can be divided in the same as way as clumpers. Examples include bee balm (Monarda), goldenrod (Solidgo), and aster (Symphyotrichum).

Plants with Woody Crowns

Plants that have woody crowns can be divided with somewhat more effort than other categories. The basic process is the same as for fibrous-rooted clumpers but typically require cutting the root structure apart with garden shears or saw, e.g., a pruning saw.

Examples of these plants include Astilbes, bear’s breeches (Acanthus), foxtail lilies (Eremurus), goatsbeard (Aruncus), lilyturf (Liriope), peonies (Paeonia), and wild indogo (Baptisia).

Plants Best Not Divided

Some plants have root structures that do not divide well: they might have single taproots or single woody roots, and are best propagated by seed. These plants can be recognized easily when they have been dug up. Examples include lavender (Lavendula), Russian sage (Perovskia), Allysum, carnations (Dianthus), Euphorbias, foxgloves (Digitalis), butterfly weed (Asclepias), and others.

Dividing perennials can be a satisfying project for avid gardeners, and the most inexpensive way to multiply favored plants to the landscape. Tour your garden in a search for division candidates. 

Planning a Cutting Garden

An ornamental garden, as contrasted with an edible garden, often will yield a number of blossoms suitable for occasional floral arrangements. To produce blossoms specifically for indoor display, however, the gardener needs to develop and maintain a cutting garden.

A cutting garden can be as small or as large as the gardener chooses. Because it serves as a “blossom factory,” it need not be a landscaping feature. It could be a rectangular space with plants in orderly and efficient rows. The bed could be as short or long as desired, but should be no more than about four feet wide, with access on both sides for cultivation, maintenance and harvesting.

The bed should follow the familiar basic standards: fertile soil with good drainage, six-to-eight hours of sunlight, and convenient access to irrigation.

A grouping of Dahlia ‘Jomanda’. Image courtesy of the Monterey Bay Dahlia Society

Plant selection should reflect the gardener’s preferences, which might be based on personal favorites, intended combinations of blossom colors, or other criteria. Unless the gardener has particular plants in mind, the initial plant selection might be based on expert recommendations.

The best source I know for such recommendations is Debra Prinzing, advocate for American-grown flowers, author of The 50 Mile Bouquet and Four Seasons of Locally Grown Bouquets from the Garden, Meadow and Farm. Here are her current top ten picks for summer bouquets:

  • Dahlia — medium-sized forms
  • Zinnia — Queen series for soft colors; Persian Carpet varieties for textural accents
  • Sunflower—‘Plum’, ‘White Night’, ‘Moulin Rouge’, ‘Strawberry Blonde’, ‘Chocolate’
  • Cosmos—Double Click and Cupcake series
  • Ammi—(called false Queen Anne’s Lace) ‘Dara’, ‘White Dill’, and ‘Green Mist’
  • Yarrow—both pure colors and muted/pastel varieties
  • Shasta Daisy—especially double forms like ‘Crazy Daisy’ and ‘Sante’
  • Roses —try some in the caramel and terra cotta range: ‘Hot Cocoa’, ‘Cinco de Mayo’, ‘Pumpkin Patch
  • Herbs— purple basil and ‘Berggarten’ sage for foliage and fragrance
  • Nigella—blue blooms, unusual seedpods, and lacy greenery are eye-catching

After the gardener has selected plants for the cutting garden, the options are to buy and install small plants at a garden center, or plant seeds. Buying small plants involves paying someone for starting the plants from seed, so it’s faster and more expensive than growing your own. But choices could be limited Planting seeds requires less expense, and also provides access to a wide range of options.

Seeds should be planted at the right time of the season. Some seeds should be started indoors in early spring; others are best planted in the ground in early spring, early summer, or mid-summer/early fall. This month is still a good time to start certain seeds for a cutting garden.

An excellent source of recommendations for seasonal planting of seeds for flowering plants is local expert Renee Shepherd. For a timely list of flowers to plant now, browse to her website, click on “Gardening Resources” and search “Time to plant Renee’s Garden Seeds.” Her seeds are among those on display in garden centers.

Seed packets typically have brief instructions for successful planting of seeds.

Flowering plants that have multiple, branching stems will produce maximum yield of good quality flowers with long stems when their primary stems are cut back (“pinched”) at an early stage of growth. Examples include carnation, cosmos, dahlia, and snapdragon.

Pinching is not appropriate for plants that produce just one flower per plant. Examples of such plants include flax, stock, and single-stemmed sunflowers.

Growing your own flowers for bouquets and floral arrangements is one of the most satisfying garden activities. A good time to start your own unique cutting garden, and beginning to gain experience and enjoy the process,  is mid summer/early fall. That’s right now!

Climbers Bring Interest and Drama to the Garden

Vitis ‘Roger’s Red’ tendrilsIf your garden needs a dramatic focal point, or a taller feature as contrast for lower-growing plants, or something that will fit into a limited space, consider a climber.

Climbers are a fairly large and diverse category of garden plants, with options for several different situations. There are several lists of climbing plants that particular gardeners enjoy. At times, it appears that some garden writers are obsessed with making lists. I try to resist that temptation and recommend instead that interested persons search the Internet for “climbing plants,” and browse through the lists that will appear on your screen. Another good resource is the Western Garden Book’s Plant Selection Guide for Vines.

There are two broad categories of climbing plants: those that thrive in full or partial shade, and those that need full sun. The shade lovers are mostly foliage plants, such as Virginia Creeper (Parthenocissus quinquefolia) and Algerian Ivy (Hedera algeriensis ‘Gloire de Marengo’). The sun lovers— a large group, too many to list— typically offer colorful blossoms.

Another important variable among climbers is their height at maturity. Some, like the Virginia Creeper and Algerian Ivy, already mentioned, can reach impressive heights, up to 150 feet. Another plant that is capable of both great heights and blossoms is the shade-tolerant Climbing Hydrangea (Hydrangea petiolaris), which can reach 80 feet. These vigorous climbers can be good choices for high walls or the side of buildings in need of decoration. I once recommended Climbing Hydrangea for a residence that was backed up to a steep slope that was quite close to the home’s rear windows.

At the other end of the scale are the climbers that typically grow to six feet or less, or that could be easily controlled to such heights. Examples include Sweet Peas (Lathyrus odoratus), Climbing Snapdragon (Asarina scandens), and certain species of Clematis, e.g. C. alpine or C. integrifolia). These climbers can be charming specimens for larger containers with a small-scale trellis.

There are many climbers that grow to heights between these extremes. As with all selections, be sure to know a plant’s mature size before adding it to your garden.

All climbers need a support of some kind in order to reach their maximum height. The necessary support depends on the given plant’s climbing method. Here are five categories of climbing methods:

Vitis ‘Roger’s Red’ Tendrils

  • Tendrils, which are wiry growths from the plant’s stems, can grasp thin supports, e.g., netting or metal grids. Examples include grapes and Sweet Peas.
  • Twiners are stems or leaves that can wrap around wires, strings, twigs, or other stems. Plants that use this method are called “bines.” Clematis, Morning Glory, Jasmine, and Honeysuckle use this method.
  • Scramblers have long, flexible stems that resemble vines, but lack a way to grip a support. Examples include climbing and rambling roses, and bougainvillea. These plants use thorns or prickles as “hooks” to assist in climbing, but they need to be tried to a trellis or other support. An interesting option for larger spaces is to use a bougainvillea as a spectacular ground cover.
  • Stickers are adhesive pads or tendrils that stick to many different surfaces. Plants that use this method include Virginia Creeper and its relative, Boston Ivy (Parthenocissus tricuspidata).
  • Stem roots are short, stout roots that grow from the plant’s stems and cling to various surfaces. English and Algerian Ivy use this method, as does Climbing Hydrangea. I planted Algerian Ivy as a ground cover and soon found it growing up a two-story brick chimney. Now I need a tall ladder or scaffold to remove it before it damages the mortar.

My garden includes a few climbing roses, one rambling rose, a sweet pea, Evergreen Clematis (c. armandii), Chilean Jasmine (Mandevilla laxa), California grape (Vitis ‘Roger’s Red’, actually a cross of a California a native grape and a commercial variety), rampant Algerian Ivy, and two Australian natives: Cape Arid Kennedia (Kennedia beckxiana ‘Flamboyant’) and Wonga Wonga Vine (Pandorea pandorana). Four of the five climbing methods are represented among these plants, save only the Sticker method.

Climbing plants bring variety to the garden, and often contribute color, drama and even challenges to the landscape. They are definitely worth a try, but as always do enough research to avoid surprises.

In Bloom in April

Gardening at this time of the year includes at least two absorbing experiences: plants in bloom and plants on sale.

Several early bloomers are already decorating the garden. I’m enjoying a Chinese Ground Orchid (Bletilla striata), also called the Hyacinth Orchid. It has been cultivated in China for 1,500 years for its medicinal properties, but it’s also garden-worthy for its blossoms.

Chinese Ground Orchid

This terrestrial orchid is very easy to maintain, especially after striving with limited success to grow other members of the enormous orchid family. It had been growing under other plants and seemed to be struggling despite its reported need for filtered shade. It was propagating, however, by producing many small bulbs. I moved the bulbs, which were already sprouting, into containers in sunny locations, and they are doing fine

 

 

 

Australian Bluebell Creeper

Another plant that brightens the garden now is the Australian Bluebell Creeper (Sollya heterophylla). The generic name refers to British botanist Richard Solly; the specific epithet means “different leaves” because the plant produces a few different leaf shapes. This is a three-foot shrub with small, bright blue flowers that are bell-shaped with some varieties; mine are more star-shaped.

 

 

 

 

Mediterranean Spurge

A third performer is the Mediterranean Spurge (Euphorbia characias wulfenii), which grows five feet high, with showy heads of chartreuse flowers and whorled blue-green leaves. This plant freely generates seedlings that are easy to pull or share.

Recent and upcoming plant sales are being listed elsewhere, so this column focuses on roaming through such sales to discover and acquire new and different specimens for the garden. I’ve been accumulating interesting additions and seeking time to install them.

 

 

Here are some of my recent additions, and their intended destinations.

At the Arboretum’s recent sale, I found a large Cape Arid Climber (Kennedia beckxiana ‘Flamboyant’), a native of Cape Arid which is in Western Australia. This vigorous, woody plant that climbs with tendrils is one of the Arboretum’s Koala Blooms selections. It produces two-inch long orange-red flowers with a showy large lime-green central spot on a reflexed petal. This plant might grow more robustly that I would prefer, but I’ve learned that it can be heavily cut back after flowering to prevent invasive growth.

This plant will replace a Canna Lily (Canna ‘Cleopatra’) that had overgrown its pocket bed, so I moved it into containers in a sunnier location. Interestingly, the canna has been described as “flamboyant,” which is also the name of this Kennedia cultivar.

I also came upon Aloe ‘Crosby’s Prolific’, which is a cross between A. nobilis and A. humilis, both of which are small aloes that succulent specialist Deborah Lee Baldwin recently highlighted as “growing tight and staying low.” I picked up three of these small plants to fill space in my South African succulent bed.

A third recent acquisition is Spanish Sage (Salvia lavandufolia). After the annual cutting back of a large collection of salvias, the need emerged for smaller plants along the bed’s border. These smaller species (one-foot high ad wide) are not widely available, so I was glad to pick up three specimens as fillers.

As stated on earlier occasions, plant hunting should be done with a specific and appropriate spots in the garden. Impulse purchases, inspired by a blossom portrait in a mail-order catalog or a real, fertilizer-dosed plant in a garden center leads to hodge-podge landscaping.

Weeding Ideas, Early Blooms

Gardening friends are pulling weeds that sprouted during our recent warm days and wishing for effective treatments. There are no quick and easy solutions to weed problems, but the longer view dictates “weeding before seeding.”

Ever optimistic, I am testing an organic pre-emergent herbicide that is based on corn gluten, a natural material that discourages the formation of roots. It’s neither cheap or 100% effective, but might be worth a try. For more information on a pelletized product, visit eartheasy.com and search for “corn gluten.” For a liquid version, go to amazon.com and search for “Green It.”

Another organic approach is the application of vinegar, which can kill really young weeds. Household vinegar (5% acidity) has some effect but horticultural vinegar (20-30% acidity) works better but dangerous to the user.

Other organic weed killers are based on clove oil will kill at least the top growth of mature weeds.

Still, the best, cheapest and most reliable way to kill weeds is pulling or digging them out by their roots.

Take a break from weeding to anticipate the coming spring and enjoy plants that are in bloom now in your garden. As I look around, I am pleased to see these early bloomers:

Wagner’s Sage (Salvia wagneriana), a large sub-shrub from Mexico and Central America has gorgeous hot pink or pink and white bracts that are greatly appreciated by hummingbirds as well as gardeners.

Wagner’s Sage

Salvia blossom - scarlet

Big Mexican Scarlet Sage

Big Mexican Scarlet Sage (Salvia gesneriiflora ‘Tequila’), another treasure from Mexico and Central America, produces brilliant red flowers with a striking black calyx and grows about ten feet high in California gardens. My neighbor has a stand of this plant that has grown fifty feet wide and well over fifteen feet high with support from adjacent shrubs.

 

 

 

 

Wonga Wonga Vine (Pandorea pandorana), from Australia, is a vigorous, woody vine that climbs with support from a tree or large shrub, or a trellis of some kind. Its popular varieties have differently colored blossoms: ‘Snowbells’ (white), ‘Ruby Belle’ (pinkish), ‘Ruby Heart’ (cream with ruby blotch), and ‘Golden Showers’ (yellow). My specimen grows on 2” x 2” rail attached to a fence and produces white racemes. The plant usually flowers in spring; we’re still in winter, so this is an early bloom.

Other plants now in bloom include

  • Beach Sage (Salvia africana-lutea), interesting wrinkly, golden brown flowers, from South Africa.
  • Winter Daphne (Daphne odora ‘Aureomarginata’), delicate blossoms, fine fragrance;
  • Common Hyacinth (H. orientalis), one of the earliest bloomers
  • Trumpet Daffodil (Narcissus ‘King Alfred’ probably), a cheerful yellow blossom
  • Blue Hibiscus (Alyogyne huegelii ‘Santa Cruz’), a large, frequent blooming evergreen shrub

A plant to watch is the Chinese Ground Orchid (Bletilla striata), which is now preparing for early blossoming. This hardy orchid, native to China, Japan, Taiwan, and Vietnam, is delightfully easy to grow. It is a terrestrial orchid that requires no extraordinary care and produces rose-mauve blossoms that resemble a miniature Cattleya orchid flower. An established clump will produce dozens of flower spikes. I recently moved several plants from too-shady spots into large shallow containers, anticipating the development of clumps in a couple years. They are not particularly frost-tender, but recent frost warnings encourage moving the pots under shelter.

As always, gardening involves the exercise of patience.