Darm Crook lives and gardens a few kilometers Southwest of Hay River, Northwest Territories, Canada. The area is zone 1 Canadian scale. His main hobby interst is gardening for which he has all the time he could ask for as he is a retired carpenter. Darm has tinkered with hybridizing lilies, Aquilegia, Roses, Delphiniums, Geraniums, Lisianthus, and probably a few other plant types. He curently has 50 or so Lilium species growing plus a few thousand hyrids of his creation, most of which winter out doors under the snow bank that is any where from 24 to 48 inches deep every year. The winter temperatures can easilly drop to -40 °C. to -50 °C. for two or three weeks, natures white mulch allows the plants to survive. He has some Iris species, and a few other bulbous type plants growing.
It's not that un-common to see plants rated to grow in zone 5 Canadian scale areas growing and returning year after year in his zone 1 gardens. His belief is if you give a plant the foundation (the right soil) it needs, if at all possible, it will grow and produce off spring, as all living creatures, plants or other wise, have a will to live and reproduce to continue their line. Of course this doesn't mean every plant can be grown in zone 1, some are simply too tender.