Plants That Complement Iris

Garden Conditions

• No plant complements another if it isn't thriving, so your first step is to assess your site and choose both the iris and the companion plants with your growing conditions in mind. Determine if the area receives full sun, part shade, or full shade. Most iris like sun, but Siberian iris will take some shade as will Iris cristata, the dwarf crested iris. Iris foetidissima, the Gladwyn iris, will take quite a bit of shade, but the flowers aren't showy. It is usually grown for its leaves and the bright orange seeds.

  Also, consider the amount of water you can give. Bearded iris take some drought, but Japanese iris, Lousiana iris and Iris pseudacorus, the yellow flag iris, need large amounts of water. Other factors to look for are soil pH and texture.

Leaf and Flower Texure

• Since the leaves of any iris are on display for far longer than the flowers, use them to create long-term interest by complementing the linear leaves with delicate, ferny leaves or flower displays. Then add some annuals or perennials with large, bold leaves and you have a focal point for the length of the season. Cosmos and coreopsis are excellent for light and airy effect, and foxgloves will give a bold, rough texture that stands out against the smooth iris leaves. You could also use Bergenia with its round, waxy leaves and gain a bonus of early blooms besides. Sweet rocket and coral bells have sprays of delicate flowers, and the large blooms of roses and peonies are traditional complements. Once you have some variation in leaf and flower texture, add other plants with medium-sized leaves to round out the picture.

Bloom Time

• When you start choosing plants for their flowers, consider extending the season of your bed with daffodils or some of the early bulbous Dutch iris. You can use Japanese iris for later blossoms, too. Daylilies and cannas are also good companions to keep the color coming in your garden. Phlox, penstemons and chrysanthemums are all useful for extending the season.

Color

• Once you know which flowers bloom at the same time as your iris, you can start playing around with color combinations. The blues and purples of Siberian iris go with just about any color and their narrow leaves suit the woodland landscapes that include azaleas, rhododendrons and Korean dogwood. Bearded iris come in a wide variety of colors and their large size suits the peonies and roses many people plant with them.