Bearded Iris
Plant of the Week August 21, 2023
Bearded Iris (Iris x germanica)
By Linda Moll, Anoka County Master Gardener Intern
Have you ever found yourself wanting something because of the good feelings it evokes? I have, especially in my garden. Peonies, poppies, daffodils, and hollyhocks have all found their way into my yard. I even find myself looking for the shrub rose my grandmother had growing on her back fence.
While I love those plants, an absolute favorite is the tall, stately, bearded iris. I can still see them lining the side of our house, with their sword-shaped leaves splayed out like living fans. And oh, the amazing flower show in late Spring!
There are over 250 species of the genius iris, including the familiar 2-3 foot tall bearded iris, or Iris germanica. Iris was the Greek goddess said to “ride rainbows.” When this unique six-petaled flower opens, you can see the fuzzy “beard” on the lower petals.
Bearded Iris are perennial in zones 3-9 and thrive in full sun, at least 6 hours a day. Plant your bearded iris 1-2 feet apart in well draining, slightly acidic soil. Drape the roots of the rhizome over a small mound of soil. Leave the top of the rhizome exposed. Planting too deep prevents flowering. Newly planted iris may not bloom the first year.
There are now varieties that bloom early, mid, and late spring. Some hybrids may even bloom twice a season. Iris have multiple blooms on each stalk. Deadheading is encouraged. When the show is done, cut the flowering stalk all the way down, but don't cut the leaves. The plant needs to maintain its leaves to continue photosynthesizing. The energy gathered through the rest of the summer is important for next year's blooms. In mid to late fall, cut the leaves back to 5-6 inches. A coating of mulch can help protect them in winter, but remember to expose the rhizome again in spring.
Iris don't like to be crowded, so plan to divide and share them every 3-5 years. Divide plants between late July and mid August. This gives them plenty of time to become established before winter.
Good air circulation is also important. Many gardeners give iris a bed of its own, but they grow well with roses, peonies, and lilies. Avoid ground cover plants near iris. A creeping ground cover can prevent blooms as it shades the rhizome.
Potential problems with bearded iris include rhizome rot, leaf spot (bacterial or fungal), and iris borer. Providing iris with the proper growing conditions will minimize most pests and diseases.
Need another reason to add this classic plant to your garden? Butterflies and hummingbirds find them attractive but not deer or bunnies!
While I've had no luck finding my grandmother's shrub rose, a few descendants of Mom's bearded iris line the side of my house today. They make me smile.