With their rainbow of colors and long bloom season, annuals are naturals for container gardens. Perennials and bulbs offer still more colorful, interesting choices. Shrubs or small trees add structure to a group of containers, while vines can form cool, leafy screens.

Containers come in a dazzling array of shapes, colors, and materials. Whichever you choose, be sure there's at least one hole in the bottom to ensure proper drainage.

Soil mixes

Plants in containers need soil that allows roots to grow easily; it should be fast draining yet moisture retentive. Quick drainage means roots won't run the risk of suffocating in soggy soil; good moisture retention saves you from having to water constantly. Regular garden soil, even if it's good loam, is too dense for container use. A better bet is one of the packaged potting mixes sold at nurseries and garden centers.

Watering

Because they have only a limited amount of soil from which to draw moisture, container-grown plants require more frequent watering than those grown in the ground. In hot or windy weather, some (especially those in hanging baskets) may need watering several times a day; in cool weather, it may be sufficient to water weekly or even less often. Check the soil in the containers and water when the top inch or two is dry.

To water thoroughly, apply water over the entire soil surface until it flows out of the pot's drainage holes. This moistens the entire soil mass.

Fertilizing

Because the necessary frequent watering leaches nutrients from potting mix, container plants need regular feeding. Apply a liquid fertilizer every 2 weeks; or mix a controlled-release fertilizer into the potting mix before planting.