When we think of combining flowers in a flowerbed or border, the first consideration that usually comes to mind is color. Do we choose warm oranges and yellows, or cool lavenders and whites? Or do we combine the two, juxtaposing orange and yellow with deep violet, for example? Of course, color isn’t the only issue. Plants have other features that we should also take note of, such as height, foliage, and, in particular, bloom time. (There’s no point in combining flowers if they bloom at separate times of the growing season.) Then, we need to ask if they have the same cultural needs—shade vs. sun, or damp vs. xeric, for instance.
But how often do we consider flower shape when pairing blooms?
Flowers generally fall into specific groups according to their shape and structure. Some have radial symmetry—think of daisies, roses, or clematis. Others have bilateral symmetry, such as orchids, impatiens, and peas. Flowers may be bells or funnels, tubes, or shaped like wheels.
When combining different kinds of flowers, try imagine pairing blooms with distinctly different shapes. On the left, California poppies are planted with ornamental “drumstick” alliums, contrasting not only their colors but also their very dissimilar shapes. The flowers on the right couldn’t be more different from one another.
Even flowers that are the same color can contrast in other ways. The petunias in the left-hand photo have large, fused petals, creating a funnel, and they’re lovely pared with lantana in the same color scheme. On the right are violas, with their bilateral symmetry, combined with creeping phlox, which has radial symmetry and smaller petals.
Another approach is to intentionally match flower shape and vary other features. Here we have Shasta and gloriosa daisies (Rudbeckia hirta), two flowers with the same shape but different colors. (Note that the warm hues of the Rudbeckia are repeated in the yellow center of the daisies.)
Creating interesting combinations is especially important when planting containers. Because the pots provides a focal point set apart from the rest of the garden, they’ll receive more attention. Why not make the most of the opportunity? The combination can be something as simple as annuals and/or perennials with flowers in a variety of shapes—as illustrated by this unusual red and white geranium, combined with red pincushion flowers (Scabiosa), and white sweet alyssum—or you can add plants with interesting foliage to introduce even more diversity.
If you’re still looking for inspiration, visit a botanic garden (if it’s still open) or browse through books and magazines, paying particular attention to combinations that appeal to you. I particularly enjoy the photos in Lauren Springer Ogden’s various works, such as her 2011 classic, The Undaunted Garden: Planting for Weather-Resilient Beauty.