It is always better in the fall, but if the plants are put in pots in a morning sun or filtered light area and given plenty of water, they should do fine. I just dug a large clump of iris a couple of days ago. When digging them, I cut the fans back to about five or six inches so as to not put too much stress on the roots and bulbs. I'm going to lift some day lilies in the next day or two. Their soil is so dry, they will likely perk up when I move them to their temporary nursery pot containers of rich, moist soil. Also am going to lift and pot quite a few hostas which are not doing well in our dry soil that is totally criss crossed with oak roots.
Eclectic gardening style, drawing from 45 years of interest and experience. Mostly plant in raised beds and containers primarily using intensive gardening techniques.