By Nan Sterman
In colder regions, massive displays of annual flowers signal the end of the dreary winter. In Southern California, however, we have color year-round. So those big displays of annuals just don’t have much meaning to us.
In fact most springtime nursery annuals are pretty thirsty plants, far thirstier than is reasonable for filling a garden or a display. Instead we satisfy our craving for annuals by growing them in pots. We treat them as mini gardens, concentrated plantings small enough to indulge with water, yet not waste too much.
A trip to the garden center now yields a wide offering of spring and summer annuals. Here are a few of the best for growing in containers in Southern California.
The general rule for well-designed containers is to include at least three categories of plants: one tall; one wide, to act as a filler; and one to cascade over the side of the pot.
Annual African marigolds fit the bill for something tall. They flower in shades of yellow to gold, orange to bronze, and are sometimes multicolor. Different varieties have different flower shapes -- pompom, single petal, ruffled, multi-layer, and more. Their fragrance is slightly citrusy. Set these taller plants to the back of the container.
Dahlias technically are perennials, but in our climate most gardeners replace them every year. The round flowers have petals arranged in a circle around a center disk, typical of flowers in the sunflower family. Recent hybrids come in almost every color of the rainbow. A collection of brightly colored dahlias looks like a sprinkling of confetti. These too are best used as the taller plants in a container composition.
Coleus, especially sun coleus, is a perfect choice for “filler” plant in a container. Its multicolor foliage helps the flowers stand out. Coleus also adds texture when not blooming.
Who doesn’t love snapdragons? The challenge is how much they love our gardens. Snapdragons do best in the drier inland valleys, away from the coast, where they soon develop mildew. They may be short-lived, but they’re lovely and oh-so-reminiscent of childhood!
Bright-blue flowering lobelia is one of the best choices for a cascading plant. It grows gracefully, spilling over the side. Its flowers are small, delicate, but prolific, and the most heavenly shade of blue! Combine lobelia with almost any contrasting color: orange, red, yellow, pink, white, even purple.
For a more textural contrast, add some grasses to your annual containers. Unfortunately, succulents don’t mix well with annuals, and neither do most low-water woody plants. They require very different growing conditions, and are incompatible with the rich soil and plentiful irrigation that make these annuals thrive.
Grow potted annuals in rich potting soil in full sun near the coast, afternoon shade in the hot inland valleys. Mulch with a 1-inch-thick layer of rounded pea gravel to give the pot a finished look. The gravel also keeps soil from splashing out when you water, and holds moisture in the potting soil.
Feed regularly with an all-purpose organic fertilizer. Deadhead regularly to prolong blooming. Water deeply and frequently. Consider placing a saucer under pots to catch excess irrigation. Enjoy your annuals while they bloom, then compost them and start dreaming about next year’s annual composition.