Great three-way combinations for container gardens

Combining three or more plants in a container is a bit like flower arranging, in that you begin with a tall, upright plant to structure the design, add a second plant that will fill out the picture with foliage and colour, and connect the arrangement to the container with a cascading plant that will gently spill over the edges. Creating container bouquets in this manner is tremendously rewarding, although it is also full of surprises. These tips will tell you more.

The lists below sorts 50 popular care-free plants into uprights, fillers, and cascading plants, but there is substantial crossover between categories because of the crowded nature of container combinations. When several plants are packed into a container, their roots compete for moisture and nutrients, and above the surface, the leaves and stems compete for light. As a result, stems are often somewhat lax and rangy, which is usually a blessing.

For example, although you may not like to see coreopsis or rose campion flopping over in your garden, when the same thing happens in a container the effect softens the edges of the container. Still, to maintain the height needed to keep a container combination balanced, it may be necessary to stake the tallest plants.

Shade is often a factor in container combinations, because window boxes and other containers placed close to the house usually receive a maximum of a half day of sun. Light limitations often cause otherwise compact plants to stretch out, becoming much more vinelike or trailing in habit.

This often happens with nasturtiums and petunias, making them do double duty as cascading plants. Vining plants, such as English ivy, vinca, and sweet potato vine, always cascade, and their foliage persists all season.

Uprights: Caladium, calla lily, canna, clematis, coreopsis, cosmos, flowering tobacco, geranium, globe amaranth, hydrangea, liriope, ornamental grasses, phormium, rose campion, salvia, scarlet runner bean, snapdragon, sweet pea, and yucca provide height.

Fillers: Ageratum, artemisia, begonia, browallia, coleus, dianthus, dusty miller, fan flower, heuchera, impatiens, lady's mantle, lantana, nasturtium, pansy, periwinkle, petunia, portulaca, rose campion, Swan River daisy, and verbena soften pot edges.

Cascading plants: Candytuft, dead nettle, English ivy, licorice plant, lobelia, petunia, sun rose, sweet alyssum, sweet potato vine, thyme, and vinca will trail gracefully over pot edges.