Growing Bearded Irises These majestic flowers are surprisingly easy to grow, and actually require less attention than almost any other garden flowers. Your iris rhizomes will arrive already growing in a small pot, with this spring’s growth beginning. A rhizome is an irregularly shaped bulbous root that grows at a right angle from the foliage. Simply remove your Bearded Iris from the pot and plant with the top of their rhizomes exposed. Once planted, the new spring foliage will continue to grow and produce gorgeous, iconic blooms. Over time, the rhizomes will spread and multiply, delivering even more Bearded Iris blooms to your planting area as the years pass.