Successful container arrangements often contain a variety of common perennial plants, which are plants that return year after year. Choose a thriller, which is a tall, upright plant; a spiller plant which will cascade over the edge of the pot; and filler, which is a fast growing plant that fills in any empty spaces in the container. When cold weather threatens, move the container into a protected area outdoors, or place it in an unheated, attached garage.
Day lilies are popular plants whose flowers come in a wide variety of colors, sizes and shapes, according to Purdue University Cooperative Extension Service. Daylilies thrive under a wide variety of growing conditions. Depending on variety, daylilies will work well as both a thriller and a filler plant whose foliage will gracefully drape over the edge of the container they are grown in. Some varieties, such as Stella D’Oro will bloom on and off all summer long, while other varieties will bloom continually for several weeks, then not bloom again until the following summer.
Lamium, or dead spotted nettle, is a natural choice for a spiller in a container garden. The white, yellow, lavender or pink flowers add color and the variegated foliage adds texture. For something really different, plant lamium in containers with dwarf conifers. The foliage of this plant remains evergreen throughout the winter, then in early spring, the small lip-like flowers burst into bloom. Lamium is a rapid grower whose mature height ranges between 6 and 12 inches tall. Plant in shade or part-shade in a container filled with well-drained acidic soil.
Heuchera, also called coral bells, is an excellent filler plant that produces small sprays of bell-shaped flowers excellent for cutting. The attractive foliage comes in a wide array of colors, including lime green, black, amber, and plum. Choose from leaves in a single color to those with colored veins or splashes of color on their leaves, such as Midnight Rose which has burgundy colored leaves splashed with pink. Plant in part-shade or sun, depending on variety, in a container filled with well-drained fertile soil. Spread a thin layer of mulch over the root system of heuchera plants, especially during the winter months, when they tend to heave out of the ground.