mulching irises for winter

Asked November 7, 2016, 5:00 PM EST

I transplanted some irises this fall and wondering if mulching with leaves would prevent them from heaving out of the ground during the winter. In the spring, I find all these plants sitting on top of the ground! Would it be best to use whole leaves or shred them first? I know they have to be removed from the plants early so that moisture does not become the next problem. Thank you.

Olmsted County Minnesota irises horticulture

1 Response

Temperature fluctuations, in combination with the proximity of the rhizome to the surface of the soil can contribute to irises coming out of the ground. Mulching with 4-6 inches of organic material after the ground has frozen can be beneficial to help prevent this. The mulch should then be removed at the start of the growing season. See below for a link with more information about care of irises. http://www.extension.umn.edu/garden/yard-garden/flowers/iris/ If you choose to mulch with leaves, they should be shredded. See below for information about mulch options. http://www.extension.umn.edu/garden/landscaping/maint/mulching.html