When designing a container, it is important to consider the distance from which it will be viewed. For example, if you are creating a container for the center of an outdoor seating area, it can be subtle. People are appreciating it from only a few feet away. If you are designing for a front entry, however, a bold statement is required. The most important element for such a composition is contrast.
Contrast is most often evident by its absence. Without contrast, combinations look messy, muddy, and unedited. Its a bunch of grassy foliage jumbled together or scads of tiny blooms competing for the spotlight. It's what makes us go, "This needs something."
Using contrast to benefit your containers is as easy as thinking in opposites. Let us start with the container itself. You've got a simple terracotta pot. How can we describe it? It's earthy, warm, old-fashioned, and unpretentious. Contrast suggests that the first plant we choose should reflect the opposite. We want foliage that is sleek, cool-toned, or modern.
Consider these options for our first plant: Variegated Water Iris, Lamb's Ear, Corkscrew Grass
Let's say we go with the Water Iris. It's upright, smooth, and variegated. We need a second plant that is sprawling, textured, and rich in color.
Second plant options: Mustard Greens, Purple Setcreasea or Heuchera
I like the dimpled texture of the Mustard. It's broad greenish purple leaves compliment the Water Iris nicely.
Finally, the splash of color is up to you. Snap Dragons and Pansies are always popular, but I suggest breaking from the pack with Nemesia! This cool season annual comes in white, lavender, and yellow. The white offers a sweet scent that will have you pining for Spring. For a slightly bigger bloom try Superbells Calibrachoa.