How late can a Queen be introduced in the north? ( Iowa)

[preciousbees]

The temp this weekend is going to be into the 60's, and I may check on some of the hives. Just wondering how late in the season can a person introduce a Queen? ( I have a few I would like to put into a larger colony) Paul

[beeware10]

I think you you have more to loose than gain. don't know the details but best to wait till spring.