Answer: It is a good idea to remove and destroy any leaves that look brown whenever they occur. Normally iris are cut back and divided in mid to late summer so that the new plants have time to root securely into the ground before the freezing weather comes. A rule of thumb for the latest planting date would be to allow at least eight to ten weeks before the average killing frost date. This fall after frost, be sure to clean up and remove as much of the foliage as you can to reduce the carry over of any disease or insect problem to next year.
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