I usually keep my overwintering chrysalids in my unheated guest room, which stays cool all winter long, but it never actually freezes in there or gets real cold. I plan on keeping my big moth cocoons in one of my cages (which has a fine mesh covering over it) on the porch, though, so they can experience the same weather conditions as the wild moths, in case there are some out there - I haven't seen any since the hurricane, but if there are any out there, they'd be few in number, and I want my lunas, prometheas, and one regal moth to be able to mate with any wildlings that may exist. I may or may not leave my butterfly chrysalids outside in the same setup - I probably will, just bring them in if we have a big freeze, which is unlikely.
I don't think the brown stick caused your last chrysalids to be brown - I've gotten both green and brown chrysalids on my black cages, and both colors on green branches -
{{gwi:529775}}
I've found that the brown chrysalids, which are more numerous than the green ones, are variable as to whether they emerge immediately or overwinter - some overwinter and some emerge right away. The green ones always emerge right away, at least here they do.
I don't know whether it's better in Zone6 to keep them outside, protected from predators or in an unheated room in your house - maybe somebody else will have the answer.
MissSherry

Ditto, everything Sherry told you about the chrysalides.

I live in zone 7, almost 6b, and most years I leave the BST chrysalides outside or in the garage. I usually have at least 20 or more overwinter. This past winter I put the container on my patio where it was sheltered but experienced all the cold weather, and we had single digit temps and snow and ice! When the weather warmed in March, all the chrysalides eclosed. Then we had a cold spell and the BSTs did not come around until June, which is late for them, as I usually find caterpillars in late April.

I have found that when I put the chrysalides in the garage, they eclose later. I think (IMHO) that this is because the light exposure as much as the temperature affects the eclosures in the spring. They don't get as much light in my garage even though the temps are the same as outside. But outside, my patio is on the east side of the house, and gets the morning sun as well as daytime sun through skylights.

It is so nice to have BSTs eclose in the spring! They usually stick around and lay eggs in the garden and start the cycle over again.

OKSandy

I have not had BSTs overwinter yet, but I do know that the brown chrysalides are very variable. I do not know what you should do with the chrysalides while they overwinter. If you don't get answers here, there might be some helpful info on an earlier post of mine on this forum, "Overwintering BST's?".
-Jmcat

Thank you all for the helpful advice.

If they continue to stay dormant I believe I will put them out in the garden in a screened box that I have.

Thanks again,

Lynn