Learn how to read the signs when bearded iris should be divided and transplanted and follow the step-by-step instructions on how to do it. Learn when and how to divide for best results. · though they are mostly care-free, these irises do need to be divided every three to five years to maximize their blooming potential. To revitalize the plant and ensure continued vigorous flowering, periodically lift, divide , and replant these rhizomes every three to five years. Irises do not grow from true bulbs but from thickened, horizontal stems called rhizomes, which store nutrients and spread new growth. These tips will help you divide bearded irises like a pro so you can enjoy even more flowers next year. · divide and move the irises in late summer or early fall, after blooming. Learn how to divide and care for your bearded irises with our comprehensive guide, covering the best times to divide , tools and techniques, after-care tips, and propagation methods. Learn when and how to divide bearded and siberian irises to maintain healthy, blooming plants plus tips for best growing conditions for both iris varieties. · keep irises healthy and flowering by dividing congested clumps. Heres how to divide irises —with step-by-step pictures. · bearded irises are one of the showiest flowers in the spring garden, and they are also one of the easiest to propagate and transplant.