Someone asked me to post an update to this since I made reference to it on Facebook. A couple of weeks ago, until just yesterday, it has been very cold and rainy in Houston. On a few of those days it was supposed to be below freezing so I moved my Milkweed plants to the garage, and all of the Monarch Butterfly Caterpillars indoors.
Raising Monarch Caterpillars indoors is not difficult, provided you have enough Milkweed and to clean the cage you keep them in.
Before I get to far, I have always assumed that extended temperatures below freezing would kill the Monarch Caterpillar. Perhaps that’s still true, but I can say with 100% certainty that one of my Caterpillars survived temperatures down to about 28 degrees with no problems.
Here’s how I raise Monarch Caterpillars indoors. I have several of those plastic containers that you get at the pet store to house Hermit Crabs or whatever. Within that container I put a couple of twigs so that the Caterpillars can crawl to the top of the cage to form a Chrysalis, and also to balance some of the Milkweed so it’s just not piled on top of each other. I place a paper towel in the bottom to collect the frass (poop). I change the bottom of the cage every day or two, and add Milkweed as frequently as needed depending on the size of the Caterpillars and the quantity. That’s it! Below are 11 Chrysalises, and 2 remaining Monarch Caterpillars whom I hope will change to Chrysalis soon as I’m running out of Milkweed.