Pansies are perennials that grow in USDA hardiness zones 6 to 8. Blooming in the fall, winter and spring when temperatures are relatively lower, these brightly colored 10-inch-tall flowers feature blooms in white and hues of purple, blue and yellow. Select companion flowers with the same sunlight, water and temperature requirements so they thrive.
Like pansies, snapdragons (Antirrhinum majus) thrive in cooler temperatures of USDA hardiness zones 7 to 9 and have similar growth habits. They grow between 5 inches to 1-1/2 feet tall and feature upright stems with white, yellow, orange, red or purple two-lipped blooms resembling long tubes. Amend the soil with rich organic matter such as compost or rotted-manure to provide these flowers essential nutrients. Pinch old flowers to encourage and prolong blooming. Plant a row of tall brightly colored snapdragons behind pansies to complement the blooms, or surround beds of similar or different colored pansies with shorter snapdragons in the same color.
Carnations feature upright stalks with 2-to-3-inch-wide blooms in a variety of colors. These flowers are suitable companion flowers because like the pansy, they too prefer cooler temperatures. Plant carnations along the border or behind pansies to form a striking background. Grow taller variety of carnations behind shorter pansies.
Winter Jasmine (Jasminum nudiflorum) is a fast-growing shrub that reaches 4 feet high and 5 to 7 feet wide. It features light yellow flowers that bloom in mid to late winter and early spring, and dark-green foliage that accentuates the brightly-colored pansies planter in front or around it. This deciduous shrub grows in USDA hardiness zones 6 to 10 and prefers well-drained and moist soil.
Wallflowers feature tiny rounded clusters of white, yellow, orange, pink or red blooms atop straight stems. Floral clusters have an airy feel about them, which is why they complement deeper shaded pansies and bring out their color and beauty.
Gerber or gerbera daisies are good companion flowers for pansies that have similar growth requirements and complement the blooms. These flowers grow as annuals in cooler climates and perennial in warmer areas. Gerber daisies feature 3-to-4-inch-wide blooms in hues of yellow, peach, pink and red. The blooms rest atop stalks that reach up to 18 inches high. Plant alternating rows of gerberas and pansies to enhance visual interest and beauty of a flower bed.