Colorful containers create mini-gardens

I love it when I round a corner and encounter a harmonious mix of plants tucked into (and perhaps overflowing) an attractive container. Sometimes it’s a quiet and subtle hello; other times it can be a loud and exuberant HELLO! Oftentimes it’s the container, itself a piece of art, that catches my eye; and then again it’s the plants, as they playfully spill over the sides or dance high above, that lift my heart and make me go WOW! But mostly, container gardening excites my sense of possibility, reminding me how with just a few plants, a container and some mixing and matching of color and texture, one can easily create a bountiful — and beautiful — miniature garden.

Container gardening has been around ever since Americans began moving from the farm to the apartment, taking nine-to-five jobs, and priding themselves on multitasking — leaving little space or time for growing things. But container gardening offers plenty of positives, too. For those with physical limitations, it’s a very accessible form of gardening. First of all, it can be moved around (or even inside in the winter). And a planted container can fill a spot with color or interest in a way that furniture or a piece of art can’t match. It also gives your creative side a place to play.

A certain amount of care and management is required, of course, and to some folks, keeping the container looking fresh and healthy may seem like a lot of work. Others, however, may appreciate the fact that the plants are easily exchanged when they become tired or the season ends. And since container plantings tend to dry out faster than those in garden beds, some adjustments involving both the container and the soil mix will need to be made. Otherwise, when you’re going on vacation, simply move the container into the shade and ask a friend or neighbor to help out.

My N.C. Arboretum co-workers Clara Curtis (assistant director of design) and June Jolley (greenhouse production manager) are great sources of information on container gardening. Thanks to them and the diligent care provided by our incredibly talented gardeners and volunteers, the arboretum is offering a seasonal landscape exhibit I call “container magic.” It amply demonstrates that combining a well-thought-out design, a carefully selected container, the right soil and fertilizer, and a consistent watering-and-grooming regime is the best recipe for a healthy display with a good chance of lasting throughout the growing season.

From the designer’s point of view, Clara stresses the importance of container placement. You can use them to accent a step, a corner or even place them inside a perennial border. Try grouping various-sized containers within a single setting. And be sure to consider the color, decoration and style of the container, choosing one that’s appropriate to the spot and in proportion with its surroundings.

When selecting plants, Clara advises making sure they’re culturally compatible (requiring similar levels of light and moisture). Choose a mix of textures, both coarse and fine. Clara also recommends a design concept she calls “busy/simple.” This has to do with the relationship between the container and its immediate surroundings. In a world of activity, a simple design gives the eye a place to rest; in a more tranquil setting, a busy design gives the eye a place to play or be entertained. So if there’s not a lot going on in your chosen spot, go for a full, active planting design. But if the site already has a lot happening visually, a simple container planting is suitable. These principles apply equally to the relationship between the container itself and the plants within it.

Finally, to get the most out of your design, Clara suggests incorporating the following four characteristics into your plant mix. Tall — include one plant that’s at least two times the height of the pot (this can also be achieved by using a trellis and a climbing vine — install the trellis as you add soil, and make sure it’s well-secured). Draping — use a plant that drapes or spills over the edge of the pot. Weaver — a plant that fills in and ties the whole group together. Focal plant — one with bold foliage or a big flower. Here are some ideas on specific plants to use:

Tall — yucca, coleus, ornamental grasses, Japanese bananaDraping — spinach, petunia, primrose, Virginia creeperWeaver — cigar plant, evolvulus, bacopa, trailing petunia, verbenaFocal — hibiscus, coneflower, bluebeard, flowering maple

June Jolley has advice for container gardeners too. “Quality potting soil is the most important piece of the equation,” she observes. “Don’t skimp on the investment. The best results come from a good quality commercial-brand soil, one that is lightweight and well-drained but holds moisture.” A wetting agent (such as Terra-Sorb) will help retain moisture (especially important when you’re not around to water); it should be mixed in thoroughly before planting. June also emphasizes an obvious but often-overlooked point about containers: Make sure they have drainage holes! Believe it or not, many pots and other containers intended for gardening don’t have holes. And since too little moisture, rather than too much, tends to be the bane of outdoor container gardens (the opposite of what happens with houseplants), go for functionality over aesthetics when choosing your container. Clay will dry out faster than plastic or resin, and while concrete and ceramic are a little more expensive, they’re durable and hold moisture fairly well. They also overwinter better. Moss-lined baskets will drive you crazy, and by midseason, they’ll require daily watering.

When and how you water depends on the plants, the season and the site conditions. If the pot is small enough that you can lift it, June recommends getting to know what it feels like when it’s wet and well-watered and then using that to judge when it needs watering. Otherwise, the time-tested method of digging down a few inches with your fingers works without fail. And finally, to keep your plants flourishing, use either a slow-release fertilizer (evenly spread over the top) or a supplemental liquid fertilizer applied regularly throughout the season. This and regular watering will help keep the plants healthy — and once the plants and their roots really start filling out the pot, it will be a necessity.

Whether you live in the city or out on the farm, container plantings can bring welcome cheer and color to your living space. They can also add that extra spice to your garden setting. During your travels, notice the many ways containers are used and what kinds of plant combinations really speak to you. And when you get a chance, plant a container garden of your own — strategically placed so it will greet you whenever you round the corner.

On Saturday, May 14, Carol Taylor will present a workshop titled “Container Herb Gardening” from 9:30 to 11:30 a.m. For more information, call 665-2492. Or visit the North Carolina Arboretum’s seasonal landscape exhibit, “A Time to Grow,” which runs throughout this gardening season.

[Alison Arnold is director of horticulture at The North Carolina Arboretum. She can be reached at 665-2492.]