California Native Roses

Rosa Californica is the only rose in my garden that is native to California. It’s a fine plant, but tends to expand its territory through underground suckers.

When I came upon a healthy specimen of another rose identified as a California native, I grabbed it for my garden and worked to learn more about it and other California native roses.

I soon discovered that my new rose, R. multiflora, is an imposter! It is a native to Japan that has become naturalized in California and much of the U.S. In eastern North America, it is considered an invasive species, and even a “noxious weed” in grazing areas. Although it has many blossoms, it is most appreciated by goats.

Roses that are truly native to California typically have single pink flowers, varying degrees of fragrance, and spiny branches. They often are found near water sources. While they tolerate some drought and shade they grow best with ample moisture and sunlight. They can spread vigorously in hospitable circumstances, but are controllable with seasonal pruning.

Here are several species, in roughly north-to-south order.

  • California Rose (R. Californica). Grows in much of California in chaparral, riparian and central oak woodland plant communities. Most widely grown native rose. This photo  is from the website of the University of California, Santa Cruz Natural Reserves.
    Rosa_californica_California_Wild_RoseAs a side note, the UCSC Natural Reserves program includes five sites, including one in Marina and one in Big Creek (south of Carmel). The five sites ring the Monterey Bay along the National Marine Sanctuary that extends the entire coastline from the Golden Gate at San Francisco south to Big Sur, between 38 and 36 degrees North latitude along roughly 122 degrees West longitude.The wide range of habitats, from fog-enshrouded redwood forest to maritime chaparral, provide an unparalleled natural laboratory for marine and terrestrial research and serve as study sites for University scientists and students.
  • Ground Rose (R. spithamea). Native to central California from the San Luis Obispo area up into Mendocino and Humbolt and in the Sierras from Tulare to Yuba. Grows in chaparral and coastal sage scrub plant communities.
  • Nootka Rose (R. nutkana). Grows in riparian areas in northern California and up to Alaska.
  • Wood Rose (R. gymnocarpa). Grows from San Luis Obispo to northern California, and in other western states, and has large fragrant blossoms.
  • Whiskey Rose (R. pinetorum). A relatively rare rose that has been spotted in northern California and in the Monterey area. Resembles R. gymnocarpa.
  • Cluster Rose (R. pisocarpa). A fairly large plant, up to six feet high, with flowers in clusters near the top. Grows in northern California to British Columbia.
  • Mountain Rose (R. woodsii ultramontane). Grows in high elevations east of the Sierras, and produces large numbers of very fragrant dark pink blossoms.
  • Mojave Rose (R. woodsii glabrata). Grows near springs in the Mojave Desert. Similar to R. Californica.
  • Baja Rose (R. minutifolia). Grows in Baja and the southern section of San Diego. It has very small leaves and bright pink flowers with prominent yellow stamens.

The information in this column was drawn largely from Wikipedia and the website of Las Pilates Nursery, a great source of information about California native plants.


This photo is from Suisun Marsh page of the California Department of Water Resources website. The photo shows Rosa Californica’s rampant growth and numerous rose hips. This plant can be controlled in a garden, through seasonal (and diligent) pruning.

0CCARosehips copy

Notes from the Field

Gardening often resembles a random walk in which every turn in the garden reveals another opportunity to pursue or problem to solve. Today’s column follows that pattern with three current topics, unrelated except for being “on gardening.”

Sulfate of Ammonia

While clearing out “stuff” I found two 20-pound small bags of sulfate of ammonia fertilizer, which is 21% nitrogen, 24% sulfur and not much else.

Sulfate of ammonia is a long way from a complete fertilizer. It provides a rapid flush of growth and green color in foliage, and is often used on lawns. (I removed my lawn about twenty years ago.)

This special-purpose fertilizer also can be used to promote the growth of other plants, shrubs and trees in the garden, but it can over-stimulate plants, encourage tender foliage that insects particularly like, and in time acidify the soil. It should be used sparingly or not at all.

Another possible use of sulfate of ammonia would be to speed up decomposition in a compost pile: Washington State University researchers found that it would also lower pH (acidify) and raise available nitrogen. However, this is an inorganic salt, produced by combining ammonia with either sulfuric acid or gypsum and calcium carbonate. My garden is strictly organic, so I will either donate my stash to a lawn lover or dispose of it as toxic waste.

Seed & Bulb Exchange

Marina Tree & Garden Club will hold a Seed & Bulb Exchange at the Marina Farmer’s Market (at Reservation Road and Vista Del Camino) on Sunday, October 20th, 10:00–2:00.

Bring seeds, bulbs, tubers or root divisions to share or find something new for your own garden. The event welcomes both home-collected and commercial seeds, flowers, vegetables and California native plants.

Bring your offerings between 10:00 and 12:00. If possible, include the plant’s common or botanical name, blossom color and other information that gardeners like to know.

The Exchange is free and open to all, with or without items to share.

Bring a friend!

Swapping Flowering Vines

Years ago, I used half-inch copper tubing to build a trellis six inches wide and twenty feet high and attached it to an elevated deck. On this trellis I grew a common Woodbine Honeysuckle (Lonicera periclymenum), a woody twining climber. I became tired of this plant, but removing it was a daunting task.

Fortunately, a tireless student came to work in my garden and soon put the honeysuckle in the green waste. Then, at a Berkeley Botanical Garden sale, I found a Chilean Jasmine (Mandevilla laxa), a climber with beautiful, slightly fragrant blossoms and more than enough exotic appeal for this prominent trellis.


This image of the Chilean Jasmine blossom is from Annie’s Annuals, a nursery in Richmond, California that supplies retail garden centers, and also offers plants by mail.

Change can be refreshing!

Ten Things to Know About Pots

Our thoughts about garden pots are mostly opinions, and gardeners can give opinions only as much weight as they deserve.

  1. Containers may be the most important part of a small garden. Invest time and resources for the best choices.
  2. Designers like big pots better than small pots. Not all designers have the same view about anything, but often, small pots produce clutter and big pots add focal points.
  3. Plants like big pots better than small pots. Small pots are fine for small plants, but larger plants hold moisture longer, and provide roots room for larger plants and plant combinations.
  4. Non-porous pots are better than porous pots. Containers need a soil mix that drains well, but it’s also important to avoid leaving the plant with no moisture. Terra cotta pots evaporate moisture through their sides; glazed pots and other non-porous containers hold moisture longer.
  5. Pots without drain holes are OK for some plants. Succulent specialist Debra Lee Baldwin says that containers that don’t drain can be used for succulents when limiting water and monitoring soil moisture.
  6. The pot’s color should work with the plant’s color. Containers with neutral colors: white, black, concrete gray and earth tones (terra cotta = “baked earth”) won’t compete with colorful blossoms or foliage. Distinctively colored glazed pots invites for analogous or complementary color combinations with plants.
  7. Pots with brightly colored patterns should be used carefully. They can compete visually with the plant, rather than leaving the plant as the center of attention. Traditional Talavera pottery from city of Puebla and nearby communities in Mexico can be featured as artwork, without a plant.
  8. High-fired pots are better than low-fired pots. Earthenware, like Mexican pottery, is fired to temperatures below 2100°F, is not strong and chips easily. Stoneware, like some Chinese garden containers, is fired to temperatures from 2200°F to 2350°F, is very strong and durable. Stoneware is often large and heavy, but over time is worth the higher cost.
  9. The depth of the pot should work with the plant’s roots. Shallow containers are suitable for bonsai and some succulents, but most containers are intended to accommodate the roots of monocot plants, which have fibrous roots. Most dicot plants have taproots, and should be planted in a tall container. Examples include windflower, balloon flower, butterfly weeds, and Oriental poppies.
  10. Plastic containers are a matter of personal taste. The best plastic pots are well designed, attractively finished, light in weight and relatively inexpensive, but purists might insist on natural materials. Black nursery cans are for nurseries.


For inspiration on planting pots, visit Southern Living’s “101 Container Ideas”

Garden centers usually have a selection of pots available for purchase, but a wider range of choices can be found at retail businesses that specialize in garden containers, and perhaps also statuary and fountains.

Such businesses in the Monterey Bay area include

If you’re inclined to travel a bit for “pot shopping,” here are two places to visit:

For distinctive, hand-crafted garden pots, visit the website of Guy Wolff Pottery

Talavera garden pots can be found in many retail shops and also on online sources, such as Direct from Mexico and Talavera Emporium. To be certain you are getting authentic Talavera Poblana, verify that the item was created in City of Puebla or in the nearby communities of Atlixco, Cholula, and Tecali.

Making More Succulents

Two recent events—the fall sale of the Monterey Bay Area Cactus and Succulent Society in San Juan Batista and the annual Succulent Extravaganza in Castroville—attracted throngs of gardeners who gained new appreciation for the variety and appeal of succulent plants, and brought home great numbers of plants.

By bringing hundreds of small succulent plants for sale at these events, the organizers provide an important service for gardeners. They also demonstrate that making more succulents is really easy. Anyone can do it!

Propagating succulents avoids the costs of buying plants, particularly for mass plantings or large arrangements that feature many of the same plants.

This practice also appeals to gardeners who want to renew a succulent plant that has grown leggy, or too large for the intended location.

A third reason for large-scale propagation is to create plants for giving or selling to other gardeners.

Popular methods for propagating succulent plants are based on stem cuttings or leaf cuttings. Today’s column focuses briefly on those methods.

Step One: Make the Cutting.

Any succulent plant that has an elongated healthy stem can be propagated. Using a sharp knife or razor blade, cut a two-to-four inch piece from an actively growing stem. Remove the lower leaves, if any, and dip the stem in rooting hormone (available in garden centers). Then, rest the cutting in a shaded location for up to a week while a callus (or callous) forms to protect the cut end from harmful microbial life.

Make a leaf cutting in the same manner: cut or break a full vigorous leaf from the upper half of the plant, dip it in rooting hormone, and allow it to form a callus.

Echeveria plants and some other succulents form rosettes of leaves. These can be cut from the plant with up to an inch of stem, and propagated just like a stem or leaf.

Step Two: Start the Cutting

Prepare a very fast-draining medium, e.g., 80% pumice or perlite and 20% potting soil, insert the cutting and place it in a warm location with indirect sunlight. Water with tap water that has had time to release it chlorine, or use distilled water. Pour gently from above or absorb from the bottom. Mist the cutting with distilled water daily and maintain a humid atmosphere with a plastic tent or other method, but let the plant dry out before watering.

Step Three: Plant the Rooted Cutting

After several weeks, when the cutting has developed roots, transfer it to a larger container filled with 75% pumice or perlite and 25% potting soil.

In a future column, I’ll describe other propagation methods, including grafting, and planting seeds, offsets or plantlets.


Here’s a project that calls for a large number of small succulents plants. I lifted this image from Debra Lee Baldwin’s newsletter, which has step-by-step instructions for creating your own similar display. I expect neither she nor Roger’s Garden will object to my use of this photo. (It helps to have a nice container on a pedestal, but Debra says, correctly, that the container should not be featured, but rather treated like the frame for the picture.


Planting Perennials

Last Sunday was the Fall Equinox, so autumn is now official and we are heading into the year’s best time for installing trees, shrubs and herbaceous perennials.

When we plant in October, ideally just before the seasonal rains begin, our additions establish their roots during the fall and winter months and prepare for spring’s burst into leaf and blossom.

Many herbaceous perennials could be planted now. We will consider just three arbitrary but good selections:

English Lavender (Lavandula angustifolia). Several good varieties are available for this popular lavender. Small plants can be started now. In the spring, promote a compact mounded form by cutting the plant back to two inches above hard wood., and repeat in the spring of the second year. By the third spring, it will have reached mature size, or close to is, and produced a generous number of fragrant blossoms. With mature plants, a second pruning in late August will help in maintaining a good form. Replace lavender plants that have been allowed to develop a rangy form.

Salvia. Garden centers and mail-order nurseries offer about 100 species of salvia, with many selections and hybrids of most species. These “super shrubs” are native to many parts of the world, principally Central and South America, Central Asia and Mediterranean Basin, and Eastern Asia. California Blue Sage (Salvia clevelandii) is a California native that grows well in the Monterey Bay area; there are many other blossom colors, plant sizes and foliage forms available. The gardener could choose from the local garden center’s inventory or develop specific targets through research in a library or the Internet, or at Cabrillo College, in Aptos, whose salvia collection has been called the worlds largest. Most salvias should be cut back hard in the early spring, when new growth can be seen at the base of the plant.

Penstemon gets its name from a long straight, hairy fifth stamen that gives the blossom the appearance of an open mouth with a fuzzy tongue protruding. This inspires the plant’s common name, beardtongue. This is a large genus native to North America, from Alaska to Guatemala. There are taller-growing species (two-to-four feet) that can be fine additions to the middle of the border, and look best in mass plantings. There are also lower-growing species that are fine for rock gardens or the front of the border. Blossom colors include white, yellow (rare), blue, violet, purple, pink, magenta, and red. A popular selection is P. heterophyllus ‘Margarita BOP’, also called ‘Blue Bedder’. (BOP means “back of porch,” which is where this plant was discovered.)

Prepare to plant perennials in October!



Several species of lavender (Lavandula) are available. The most popular garden varieties are English Lavender (see above), French Lavender (L. stoechas or L. dentata) and Spanish Lavender (L. stoechas, L. lanata or L. dentata). There is also Egyptian Lavender (L. multifida). All Lavenders flourish best in dry, well-drained, sandy or gravelly soils in full sun, and require no fertilizer and good air circulation.


Visit Cabrillo College’s website of salvia information, and browse through the several pages for the collection, the photos of selected salvias, the chart of several species, and the Cabrillo cultivars.

Another exceptional resource for both information about, and purchases of salvias is the website of Flowers by the Sea, a mail-order nursery in Elk, California (which is about fifteen miles east of Fresno). Owner Kermit Carter tells me that Flowers by the Sea currently offers 369 species and varieties of Salvias, which is extraordinary indeed.


To learn more about Penstemons, start by visiting the website of the American Penstemon Society, which has solid information about cultivating, propagating, and identifying plants in this large genus from North American and East Asia. 

Another good source of information is the website of Las Pilitas Gardens (located in Santa Margarita, California), particularly the page titled, California “Penstemons That Grow in DRY Areas.”

The best online information on almost any gardening subject is Wikipedia. Visit its webpage on the genus Penstemon for impressive details including a long list of species, and a list of Penstemon cultivars that the Royal Horticultural Society has honored with its Award of Garden Merit.


Designing With Succulents

Gardeners who become interested in succulent plants might become a bit puzzled by their unfamiliar character. They often bloom, but their flowers are short-lived and less important than their forms and textures. They grow in unexpected ways, sometimes with branches and sometimes without. They might seem native to hot, dry environments, but some thrive in partial shade and are even subject to sunburn.


Many books about succulents are reference works, focusing on genera and species, but providing little guidance on how they can be grown successfully, propagated, displayed in the garden, or incorporated in creative works of art and craft.

Enter the succulent gardening expert, Debra Lee Baldwin, and her new book, Succulents Simplified: Growing, Designing and Crafting with 100 Easy-Care Varieties (Timber Press, 2013).

Baldwin describes this book as a prequel to her two earlier books, Designing with Succulents and Succulent Container Gardens. The new book is an overview and guide for novices in the world of succulents, and an introduction to design ideas from Baldwin and other specialists.

The book is organized in three parts. “Enjoying, Growing and Designing with Succulents,” begins with an appreciation of succulents’ shapes, textures and color, presents basic methods for the cultivation and propagation of these plants, and offers core concepts for designing succulent displays in containers and in gardens. This part alone will add greatly to the novice’s confidence in working with succulent plants.

The second part, “How-to Projects that Showcase Succulents,” includes step-by step instructions for eight imaginative craft projects using succulent plants or cuttings. Each of these projects could be varied by using different plants or accessory items, and thus does not constrain the crafter’s creative expression.

In the final part, “100 Easy-care Succulents,” Baldwin describes her 100 favorite succulent plants, based on her practical experiences in growing, propagating, and designing with succulents, as well as in teaching others how to succeed with these plants.

Large clear photographs show the plants, demonstrate design concepts and explain the development of craft projects. The photos, by the author and other succulent gardening specialists, are great resources for gardeners who learn from visualizing plants.

Baldwin expresses her enthusiasm for succulent plants, shares her extensive experiences in growing and designing with them, and provides ideas and tools gardeners need for enjoyable and successful work with succulents.

Succulents Simplified will be a valued addition to the gardener’s bookshelf.


The craft projects in this book are as follows:

Succulent Cake-stand Centerpiece – A display of succulent cuttings on an elevated plate

Succulent Squares – Symmetrical plantings in home-made shallow square containers

Living Picture Vertical Garden – Hanging displays of  succulents in boxes up to 18″ x 24″

Low-light Dish Garden – Succulents selected for low-light situations

Hanging Basket of Mixed Succulents – Using a wicker basket as a hanging planter

Succulent-topped Pumpkins – Growing succulents in a hollowed out pumpkin

Succulent Topiary Sphere – Techniques for a spherical planting of succulents

Special-occasion Succulent Bouquet – Using succulents in a corsage or boutonniere

Multiply by Dividing

September calls us to divide our herbaceous perennial plants.

We divide these plants for one or two or three reasons:

First, the plant has become too large for its space, crowding other plants or even spilling into a walkway. When encountering such situations, remember to install new plants with their mature size in mind.

Second, the plant needs room to grow, produce blossoms and stay healthy. Many perennials need to be divided every three or four years, or will reduce blooming or become misshapen. Ideally, divide your plants when they are still at their best.

Finally, you want more of the same plant, either to place elsewhere in your garden or to give to friends. Dividing perennials yields new plants quickly and with little effort, and at lower cost than any other method except planting seeds.

Schedule a division project for cool weather, and water the plant in advance to make digging easier. Plan to replant the divisions soon, or prepare to store them in shade and kept moist.

Dig a trench around the plant, at the edge of the branches (the drip line). This will sever the longer roots cleanly, and retain the plant’s primary roots.

After trenching, dig under the plant from several angles, and lever the plant out of the ground. When dividing a large plant, slice from above to cut the root ball into two or four sections for easier handling. Re-fill the hole with compost.

Once the plant is out of the ground, decide whether to plant large or small divisions. Large divisions, e.g., halves or quarters, when replanted, will yield a full specimen in a single season. Many plants can be divided into many small plants that will grow quickly, but take longer to reach mature size.

In making this decision, remove the soil from the roots by gently shaking or washing, and examine their structure.

Perennial root types include offsets, surface roots, taproots, underground running roots, and woody roots. Dividing each of these requires a specific method that may be obvious upon inspection but for more about these methods visit

Select healthy divisions for replanting or gifting. With perennial plants that develop a dead center, discard that section and choose divisions from the outer sections. Also discard any divisions that appear broken, weak or diseased, or that have minimal roots.

Plant the divisions where they will have their preferred exposure to the sun and space to grow to mature size. Dig a hole large enough to spread the plant’s roots, water in and keep moist until the rains begin.

Dividing herbaceous perennial plants can be a productive and satisfying project for the early fall.

Enjoy the season!


Fine Gardening magazine has posted Janet Macunovich’s helpful article on dividing perennials, including lists of specific categories of plants that should be divided in particular ways, as well as a few perennials that are best not divided.

The same magazine has posted a series of short video recordings that demonstrate methods for dividing perennials with different root types.