Hi Sbg, I have never grown these, but as it's in the Iris family, I should think it will be ok if planted in well draining soil, as you know the USA zone system doesn't really apply here, as their winters are usually a lot drier than ours, even if colder, so I think if anything would cause you to lose it, it would be wet, and not cold, Derek.

that's a good point Derek. Gritty soil is the order of the day then. The compost it has been grown in has a lot of perlite in it.