Breeding butterflies in the winter

A Zebra Longwing butterfly that has just emerged from its chrysalis around an hour or 2 before the photo was taken.

It's almost May, and here in Pennsylvania there are butterflies flying in the wild and in our flight houses. Currently, we have a very limited variety of species, but we hope to expand our collection throughout the summer.

While it isn't the best temperatures here for butterflies, our indoor greenhouses with artificial humidity and heating allow us to raise and breed butterflies for the entire year, even in the dead of winter.

A 5th-instar Queen caterpillar being raised on Swamp Milkweed that was grown indoors for the winter times.

The only butterflies that we breed in the winter are butterflies that cannot go into hibernation (such as Longwings, Queens, and Polydamas Swallowtails). All of our other butterflies are left outside or in a cooled environment so they can overwinter and hatch in the spring, and also so we don't have to be taking care of so many varieties of species while we have a limited supply of food.

3rd and 4th Zebra Longwing caterpillars that are being raised on a cutting of a Passion vine plant grown inside for the winter.

We grow our plants that we use for the winter times inside from seeds in early February. We let the seeds grow and grow until around late October once we have to move the butterflies inside for the winter. By that time, they have lived through a season and are established, big plants ready for caterpillars. We usually plant around 45-60 seeds of one plant to ensure that there will be plenty enough foodplant for the caterpillars during the winter and early spring. We only grow foodplants for the species that we breed during the winter, and we also grow nectar plants so that the butterflies have flowers to eat (we also give them fruits, and sugar water).