Irises: New iris, 1 by

wrote:
Anyone planting irises now in zone 4 need to mulch them. I found thta losses happens when irises didnl't get a chance to become established before freezing weather. The alternate freezing and thawing tears the roots so they heave out of the soil.

You can put flat stones on the planted iris. I usually plant my iries a bit deeper than recommended. I also don't plant or divide past mid-August.

Any mulch should be placed after the ground freezes.

Below is Edith Wolford