Gardening in Containers

Planting in containers can be a complement to planting in the ground, and it has multiple appeals:

  • alternative to garden space that’s limited (or lacking entirely);
  • opportunity for creative combinations of pots and plants;
  • supports either long-term or seasonal displays;
  • freedom to hide pots with plants after blooming;
  • design strategies for paved areas, like decks and patios;
  • ideal use of wide stairways; and
  • invites large and dramatic arrangements;

Container gardeners soon develop their personal likes and dislikes, but if this approach is new to you, here are ideas to consider.

Plan plants and pots as complements: One method is to choose a container that you like, and then find a plant that would work well with it. The reverse strategy can work too, but there are more plants than pots, so it’s easiest to find the right plant for a given pot. Find complementary colors, textures, and sizes. (One rule of thumb: the plant ‘s mature height should be about twice the height of the container.)

Think big pots: For a striking presentation, select large pots. A collection of one-gallon plastic nursery pots will minimize cost, but will also minimize impact. Smallish decorative containers, even when individually attractive, still under-sell the horticulture. Big pots produce big results, and provide more root room and hold more moisture between watering sessions.

Think multiple pots: Just like planting in the ground, mass effects can be pleasing to the eye and satisfying to the soul. A substantial array of containers can present an eye-catching display. Three is better than two, and, given lots of available space, fifteen is better than twelve. Multiple-pot displays could emphasize annuals or perennials, and can be particularly effective with bulbs.

Plan the overall look:  It’s too easy to accumulate both plants and pots one at a time, which leads to a confusing conglomeration. Such groupings reflect piecemeal landscaping, which is all too popular and ultimately minimizes bang for the buck. The first step in planning for multiple pots emphasizes the overall effect, even when limited time and resources requires building the display over weeks or even months. The plan should encompass the style of the containers. They need not all be the same, but they should work together. A Talavera planter probably will look out of place among several terra cotta pots. The plan also should also consider blossom color combinations, e.g., complementary, analogous, triadic, etc. Search the Internet for “color harmonies.”

Plan individual containers: An important difference exists between a floral arrangement, and a container that plays a role in a larger display. When planning a standalone display, the “thriller, filler, spiller” design works fine. When planning for a big, dramatic effect, however, plant each container with one type of plant in one color. And fill the containers: for example, a 12-inch wide pot can accommodate up to 30 bulbs. A more timid installation will look, well, timid.

Consider the passage of time: When building a display of seasonal plants, keep their bloom period in mind. When blooms have faded, move the containers out of sight and bring in different, ready to bloom containers. An intermediate approach involves installing layers of bulbs with successive bloom periods. This requires some planning, but the extended display can be gratifying.

Large-scale container planting takes some research. If you are considering a display of bulbs, right now is the time to order bulbs to be planted in the fall, for spring blooms. One good online resource is Brent & Becky’s Bulbs. I’ve had the pleasure of having dinner with Brent and Becky Heath, so I’m partial, but there are other very good online bulb nurseries, some of which offer wholesale prices for container gardening on a larger scale.

For design inspiration, search the Internet for “bulbs in containers,” and select “images.”

Do you have a suitable space for container gardening?

Appreciating Bonsai

This weekend, the Santa Cruz Bonsai Kai presents the 2018 Bonsai Show, the 30th annual exhibit by this local group. This show offers an excellent introduction to the art of bonsai and the beginning of the appreciation of this ancient form of gardening art.

Bonsai began in China in 2000 or more years ago and spread to Vietnam and Japan, where it grew in popularity. The most basic concept of bonsai is to grow a tree in a container while keeping it small. From that core idea, the practice bursts into an extraordinarily complex art form. Japanese bonsai master Masahiko Kimura, speaking of bonsai and Japanese garden design generally, observed, “In western gardens, it’s all about how it looks. The Japanese have stripped this away and reduced it to your imagination.” This suggests bringing your creativity to the bonsai viewing experience.

Here’s a quick overview of the art of bonsai:
Plant Selection—A wide range of trees can be used, but temperate climate trees are preferred because they grow best outdoors, where projects are developed traditionally. Selections are based on attractive appearance and adaptability to bonsai treatment. Three of the most popular varieties are Japanese Maple (Acer palmatum), Bodhi tree (Ficus Religiosa), and Rock Cotoneaster (C. horizontalis).

Container Selection—Glazed or unglazed ceramic containers are most widely used. The size and shape are based on the intended size and style of the full-grown bonsai tree; straight sides are an important criterion, often, to facilitate lifting the plant for root pruning.
Style—The style of a bonsai tree typically describes the orientation of the tree’s trunk. A dozen or more basic styles have been described, and are sometimes combined in a single work. Popular styles include formal upright (chokkan); informal upright (moyogi); slant-style (shakan); cascade-style (kengai); and root-over-rock (sekijoju).

Size Objective—The most often seen bonsai trees are medium-sized, i.e., 12-to-36 inches high, including the container. Some specimens are large (up to 80 inches high) or miniature (as small as 1-to-3 inches high).

Control Techniques—Practices to control the size and shape of the tree include trimming the leaves or needles; pruning the trunk, branches, and roots; wiring or clamping branches and trunks; grafting new material to the trunk; defoliation for short-term dwarfing, and deadwood techniques to simulate age in a bonsai.
Cultivation—The basic methods for maintaining the health of a bonsai tree will be familiar to gardeners: soil composition, fertilization, watering, and re-potting. When bonsai master Kimura was asked if you need instructions to care for a bonsai, he replied, “Do you need instructions to look after a baby?”

The Bonsai Show will be presented on Saturday and Sunday, April 13th and 15th, at The Museum of Art and History, 705 Front Street, Santa Cruz, from 10:00 a.m. to 5:00 p.m. each day. Show Chairman Edward Lambing advises that in addition to the display of fascinating plants, the event includes bonsai demonstrations and sales, raffles, door prizes, and the drummers of Watsonville Taiko. Admission for both the Museum and the Bonsai Show has been reduced for this weekend to $5.

This Bonsai Show is a fine opportunity to broaden your gardening perspectives and enjoy the creations of local bonsai artists.

Landscape Uses of Plant Containers

Plant containers are popular as decorative elements in the garden. A well-placed large pot can provide a focal point, and a strategically arranged series of pots can lead the eye throughout a planned tour through the garden.

The color of a container can also contribute to the aesthetic of landscape by complementing plants in or near the container or by creating a visual exclamation point in a primarily green environment. Many containers in the garden marketplace are neutral in color, but bright hues are readily available as well, and color patterns have been appearing in recent years.

Containers provide familiar artistic forms in the garden, and can also support plant growth. Empty containers can stand alone as artworks, as well. Containers of all sizes can function like sculptures at more affordable prices.

Gardeners also experiment with other low-cost alternatives to sculptures: bowling balls, wine bottle trees, farm equipment, and porcelain accessories of the home have been striking and even unforgettable sights in some gardens.

A novel use of plant containers could be as elements of a thematic landscape.

In these columns, I have from time to time advocated a thematic approach to garden design. Many possible themes could provide an identity for some or all of a garden, and thereby support a rationale for plant selection.

Garden themes oriented to a single plant genus, e.g., roses, irises, dahlias, are quite familiar. Other themes emphasize a color combination, or one color, like the historic white garden of England’s Sissinghurst Castle.

My garden has several thematic beds. The largest beds are dedicated to each of the world’s five summer-dry climates: the Mediterranean basin, South Africa, southwestern coast of Australia, the central coast of Chile, and coastal California.

These beds might need to be identified for visitors, because most will not immediately recognize the origins of plants. I have considered placing an identifying sign in each bed, but would rather avoid that institutional look.

Another method for identifying a geographically defined bed might be to place in the bed a large container from that part of the world. Assuming that the visitor will recognize the container’s country of origin, it might serve to identify the bed.

To date, that idea has succeeded in exactly one instance. A Talavera pot now marks a bed of succulent plants from Mexico, which is not one of the world’s summer-dry climates.

The accompanying photo shows this pot with a young specimen of Agave applanata ‘Cream Spike’, from Mexico.

Cream Spike Agave

Many garden centers have at least a few Talavera pots. Authentic Talavera pottery comes only from the very old city of Puebla, in southeastern Mexico, but many products come from other sources. Regardless of authenticity, Talavera pottery is strongly associated with Mexico.

A fairly good marker for the bed of plants from the Mediterranean basin is a terra cotta container that suggests a Mediterranean style, confirmed by an image search of the Internet. The casual visitor, however, might find its message to be ambiguous.

Garden centers offer a good variety of plant containers, but few refer clearly to a country of origin. For example, the city of Pomaire, south of Santiago, is famous for its pottery, but when taken out of context, the pots do not identify as Chilean.

My search for thematic plant containers has yielded information about the world’s pottery traditions, and concluded that there is no good substitute for a sign. My next step is to try hanging clay nameplates on the pots. I’ll report on that approach in a future column.

Gardening can lead us in unexpected directions!

Choosing Plant Containers

When choosing a container for an indoor plant, consider both practical and aesthetic factors.

The challenge to successfully match a pot and a plant could arise in two ways: you want an exceptional pot for a fine plant, or you want a find plant for an exceptional pot. In either case, the objective is a prominent display and you want the pot and plant to complement each other.

If you have a large number of plants in containers, the individual specimens tend to be lost in the crowd, and the containers might all be the same.

Rather than taking an abstract view of such decisions, let’s examine a case study of finding the right pot for a particular plant.

This is not fictional scenario, but a real-life challenge to select the right pot for a particular plant.

The challenge originated when a friend persuaded me that a freshly planted wall in my home should have an Amazon Lily (Eucharis amazonica), from central and South America. The generic name combines two Greek words meaning “good, true” and “loveliness.” The plant has impressive features: glossy, dark green evergreen leaves; plentiful white, daffodil-like blossoms; sweet and spicy fragrance; and no serious problems from pests and diseases. Because it prefers indirect light, it’s well suited as a houseplant.

Eucharis amazonica

Click to Enlarge

 

 

Here is an example of the Amazon Lily, from aJanuary 2011 article in the Shreveport Times.

 

Screen Shot 2015-05-09 at 10.58.34 AM

The Amazon Lily will grow to 18-24 inches high and wide in maturity and can remain in its pot, root-bound and happy, for many years.

This suggests a pot just large enough to accommodate the root ball and provide stability for the plant, while not requiring much soil to fill the space.

In addition to its capacity, the height of the pot should be considered. While there are no firm rules for pot height, a good starting point would be one-third to one-half of the plant’s mature height. In this case, we should choose a pot that is nine or ten inches high.

Pots suitable for houseplants are available in various materials: terra cotta, glazed clay, plastic, metal, etc. Many favor terra cotta pots, which are are widely available and inexpensive. Their porosity allows oxygen to reach the roots of plants, but also allows the soil to dry out quickly. Other materials are better for retaining moisture.

Both glazed clay and plastic pots offer many options of color and decoration. My preference is for glazed clay because it has more weight to stabilize the plant. Plastics in any form have negative impacts on the environment.

Notice that we are not considering black plastic nursery cans for houseplants!

Color is another consideration for the choice of container. Here are some options.

  • Monochromatic scheme: Given the plant’s striking, ever-present leaves, one or more shades of green would be ok. A simple dark green would provide a visual match.
  • Analogous scheme: This approach uses colors that are side by side on a color wheel. Starting with green (to go with the leaves), other colors might be blue and yellow.
  • Contrast Scheme: Create vivid contrast with three colors that are far from each other on the color wheel, e.g., blue-green, red-violet and yellow-orange.
  • Complementary scheme: The most dynamic combination uses two colors that are opposites on the color wheel, e.g., green and red.

When displaying a plant, it is generally best for the plant rather than the container to be the focus on attention. A pot that deserves to be featured should not contain a plant!

My choice is narrowing down to a dark green glazed clay pot that is no more than ten inches high. There are many possible choices with those features.

Very quickly, I found a pot that meets this objective. That was a surprise, because I had been looking off and on for a couple weeks, without success. Soon, I’ll post a photo of that pot (but I’m off to a garden tour right now).

Gardening with Succulents

The continuing popularity of succulent plants is based on several kinds of appeal, beginning with drought tolerance and including interesting shapes and an amazing range of colors.

This diversity occurs because plants in many genera have developed the capacity to store water in their roots, stems or leaves. Their common characteristic is that they live in areas where drought conditions happen often enough to make water storage essential to survival.

Succulent plants have a reputation for being easy to cultivate, relative to other perennial plants. In addition to needing water only occasionally and in small amounts, these plants are have few problems from pests and diseases.

The native environment of a succulent plant can be important to its cultivation. Most gardeners know that succulents need fast-draining soil to avoid root rot, and grow well, if slowly, in nutrient-poor soil. These plants have evolved under such conditions, and now depend upon them.

Another consideration is the elevation of the plant’s native environment. Succulent plants that have evolved on mountains are accustomed to those environmental conditions, and could have unique leaf anatomy and photosynthetic characteristics.

Good gardening practice often involves matching—or approximating—the plant’s native environment, but changing the elevation of one’s garden is not among the options. Happily, most succulent plants from high elevations can grow well at lower elevations.

Succulent plants grow in many areas of the world, and an important issue of native environment is the hemisphere in which the plant evolved. This determines the plant’s dormancy, which influences the gardener’s cultivation practices.

Succulent plants that have adapted to the northern hemisphere  are Winter Dormant:
they rest from November through February and grow from March through October.
Many plants also will rest for a few weeks of hot weather in the summer, and grow
again in September and October. Popular succulent genera that are Winter Dormant include Agave, Echeveria, Euphorbia, Lithops and Pachypodium.

Succulent plants that have adapted to the southern hemisphere are Summer Dormant, which also means that they are winter growers. Their rest period continues from May through August; they grow slowly during the winter months, and then grow actively during autumn and spring. Examples of Summer Dormant succulent plants include these popular genera: Aeonium, Aloe, Cotyledon, Crassula, Dudleya, Gasteria, Graptopetalum, Haworthia, Kalanchoe, Pelargonium, Sanseveria, Sedum and Senecio.

The gardener should avoid disturbing succulent plants during their dormant periods. So, repotting, pruning, or taking cuttings should be done in March for Winter Dormant plants and in August for Summer Dormant plants.

Watering succulent plants is another practice that is dormancy-related. When plants are dormant, they stop growing but continue to transpire, and therefore need replacement moisture. Not watering succulent plants while they dormant is the most common cause for failure.

The amount of moisture needed during dormancy depends on the dryness of the particular environment. Winter Dormant plants might need watering once or twice per week. Summer Dormian plants, which rest during the hottest time of the year, could need more frequent watering.

Also, remember to group plants with similar water needs. Such grouping can be important when combining succulent plants in containers: keeping Summer Dormant or Winter Dormant plants together will enable more convenient and more appropriate irrigation.

Mixed Succulents in Pot

Mixed Succulents in Container
(click to enlarge)

These guidelines could need adjustment for individual species; as always with the plant world, general rules are subject to variation.

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.

More

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.

More

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.

 

Contain Your Garden

For a break from maintaining your plants in the ground, and an opportunity to add interest to your landscape, try container gardening. Growing plants in containers gives gardeners many of the challenges and rewards associated with landscape gardening.

Container gardening projects often begin by identifying a spot for a focal point. This might be next to the front door, in the corner of a balcony or patio, at the end of a garden vista, or any of several other locations.

Other projects begin with an attractive container, possibly one already in the gardener’s collection, found online or in a garden center or even discovered in an antique shop. Choose from glazed ceramic, cast iron, cast stone, terra cotta, or even molded plastic; actually, any object that holds planting mix and drains water will do. Get creative!

Certainly, a container project could begin with one or more plants that inspire the vision for a pleasing display.

Container gardening novices need practical experience to generate confidence and stimulate ideas. For a good first step toward that experience, plant one plant in a twelve-inch wide container of your choice.

For the next step, plant three plants in a larger container, up to eighteen to twenty-four inches across. This project adds a flurry of variables, but a popular strategy uses one each of three kinds of plants:

  • Thriller: catches the eye with a big, bold and beautiful centerpiece.
  • Filler: grows lower and complements or contrasts with the thriller.
  • Spiller: sprawls over the side of the container, and softens the composition.

In this approach, plenty of options remain. Spend time at the garden center to consider possible combinations of color, texture and size. Feel free to assemble plants to see how they look together (put back those you don’t buy!).

When ready for an advanced project, select a large container, up to thirty-six inches across, place it at its ultimate destination, add planting mix, and add your selection of plants.

Basic guidelines for all these steps of container gardening: (a) use fast-draining planting mix, not garden soil; (b) include several plants, for a lush appearance, (c) keep the container watered, especially in hot weather, and (d) some displays are better than others, but there are no mistakes.

Enjoy your container gardens!

More…

Explore the Internet to learn more about any aspect of container gardening. Here is a selection of useful websites to start with:

The Container Garden Picture Gallery provides photos of dozens of examples of container gardens, including several in unconventional containers. Most examples identify the plants that were used, but this site offers ideas, not “how-to” advice.

Home and Garden Television (HGTV) provides 307 articles (really, not a typo!) on all aspects of container gardening. The answers to your questions must be available somewhere among the HGTV articles on Container Gardening!

HGTV video clips on Container Gardening is a collection of brief video recordings showing skilled gardener’s techniques. Some of us learn better by watching demonstrations than by reading articles. (In fact, the absolutely best way to learn gardening methods is by doing them yourself!)

If you are feeling “crafty” try your hand a making your own unique, rustic-looking Hypertufa planter. Here are the step-by-step instructions for creating a container with a mixture of peat moss, perlite and cement called hypertufa.