When I know they have such a short time left anyway, I just let the frost take them. I usually only plant icicle pansies in fall, and I've done ornamental cabbage too. You can only fight Mother Nature for so long.
Fall is always a busy garden season for me. I try to get all perennials cut back, sometimes divided or moved if necessary. I yank the annuals. Collect and hoard fall leaves... a busy time. Lots to compost.
Karen
