First question is how deeply the solidly frozen ground goes. Three, five, eight inches deep? I'm not familiar with your area at this time of year.

Been there. Done that. We came up with some odd things that worked really well. There are some possibilities, but the methods really depend on how deep the solid freeze goes. If you can, find out out deep the solid freeze goes under the grasses/irises and also under the garlic, which might not be so deep-frozen because of the straw mulch.

I will do some checking and find out how deep it goes. Thanks.

I've been trying to remember the details of some of what we did....

Luckily, all the things you still need to lift are fairly shallow-rooted.

We tried something for a couple of discrete clumps of perennials that might work for your grasses. We scraped away the snow as much as possible, and cut back the aboveground portions fairly short. Then we got out the barbecue grill, and started a good-sized pile of briquettes with a bit more fluid than we would ordinarily use. Got them glowing *really* well, and then shoveled a discrete ring of coals fairly close around the plant, with the inner edge of the ring maybe 6-8 inches away from the aboveground clump, depending on the size of the plant. You don't want to have just a wimpy ring of heat. You want a pile at least four inches wide by three inches high, all the way around.

We had only about a 3-4" depth of solid frozen soil, and only used the one treatment. When the coals were almost spent but still pretty hot, we were able to scrape away the coals in a part of the arc and get a shovel in and under. The whole plant came out, sort of in its own 'rootball'. The ground deeper under the plant was not fully frozen. They did make it, transplanting in the spring.

If the frozen depth is more than 3 or 4", you might have to add more coals and keep the process going longer. Could also do the same thing with a ring of standard woodfire, but it would take a lot more tending.... I preferred going inside for a bit of lunch, and letting the coals do the work .

This wouldn't work easily for the iris or garlic. We did come up with a method that worked for Solomon's Seal and peonies, which might work for your iris. But how big is the patch of iris? A dozen rhizomes? Or a huge patch of them? How many iris are you looking at, and how closely together?