Firebird Agastache

We have a firebird agastache in our garden and wonder how or if we can protect it over winter, or if we should still attempt to bring it in, it has grown quite large, and has been blooming from the moment Spring was in the air. As winter is in the air now, we would like a response from you as soon as possible, we would loath to lose it.

We use to think that Firebird agastache was a tender perennial in our zone 5 in Goodwood. However, it survived our winter last year (1997-1998), albeit a very mild winter.
If you want to try to winter it outside, try covering it with a mulch of straw or dead leaves held down with branches after the ground is frozen but before the first permanent snow fall. There are no guarantees! But we are encouraged by last winter's success.
If you can't risk your plant, you will need to dig it up, prune it back, and try to winter it in a sunny window. This can be done, but it is not without risks. For the average gardener, the risk of loss is about the same both ways (outdoors vs. indoors).