When can I cut back the leaves of my irises? They are in front of plants that will be blooming in summer.
—Betty Rorman-Kelley, Park Rapids, MN
You shouldn’t trim iris foliage until fall unless it is badly damaged or diseased. It needs to remain all summer to gather energy (through photosynthesis) to store in the rhizomes for future growth. In fall, cut the leaves back, leaving “fans” about 5 or 6 inches long. While you’re at it, clean up any plant debris in the area. This helps reduce the likelihood of iris borers overwintering.
If you’re worried about their foliage hiding other plants in summer, move the irises to a different spot. It’s easy to transplant them any time from mid-summer to early autumn. They need plenty of sunlight and well-drained soil, but are not fussy otherwise. Plant rhizomes horizontally about 8 inches apart, barely below the soil surface. Make sure you mulch particularly well the first fall after transplanting.