How to Divide Your Irises

Are your Irises no longer blooming as well as they used to? Are the plants getting crowded and weak? If so, the clump is probably in need of division. Now is a great opportunity to multiply your Irises for giving away to friends, expanding your own iris patch, or even to sell your irises if you are an entrepreneur.

The Irises go into a state of semi-dormancy during the hot summer months. On the East Coast this would be during the months of July and August. When the new leaves in the center of the iris diminish in size and the plant growth slows noticeably the irises are ready to be divided.

Now is also a good time to sort out any mixed colors of Irises; as Irises are usually more impressive when in clumps of separate colors. When dealing with a mixed iris patch, the best way I've found to identify the different iris colors is to tag the iris stalks when they are in bloom. I cut rags of different colors into thin strips and assign a color to each variety of iris. Then when it is time to divide the clump, any rhizome connected to the bud stalk is the assigned color. All unmarked Irises (and there will be plenty) can be replanted for identification in following years.