Not sure how it will fair the winters but they are a great host for lots of butterflies. You may find you will need more to feed all the caterpillars, if you so choose.

SCG

That looks a lot like Artemisia "Powis Castle", and I know that one is hardy....so if your rue plant doesn't make it, try Artemisia. It got a bit weedy for me and I didn't like the smell, so I don't have it in my garden anymore.

It appears to be about a Zone 4 hardiness. Certainly worth trying if you have a nice and sunny protected spot near the foundation. Seeds are always available at Richter's Herbs

Here is a link that might be useful: Richter's

Thanks so much, pudge! I appreciate the information and will see whether I have a spot for it, or whether I should leave it in the pot to overwinter. My problem is that all of the areas by the foundation are south facing - though it's very sunny, there is hardly any snow cover during winter so it may not be the best spot for borderline plants. Let me think about that more. Thanks again!