Last summer we raised several different kinds of caterpillars all the way through to butterflies and moths. Our favorites are black swallowtails. (You can watch our little video here, its not letting me post it in the blog)
If you find the little caterpillars or the eggs in your garden like we do, you can carefully take them out and feed them separately to observe their metamorphosis into butterflies.
Here is what we do:
We find the eggs and tiny caterpillars on our dill and parsley plants. If you don't have an herb garden, but know someone who does, Im sure they would be more than happy to let you take the caterpillars and spare their herbs. The eggs are super tiny, so you may only notice them once they have hatched and are little black caterpillars. These caterpillars also like to eat carrot tops and fennel. If you don't have these herbs in your garden to continue to feed your caterpillars, you can purchase store bought parsley. They don't seem to mind either way.
We use a critter cage purchased at our garden center. It looks similar to this one. You can also use glass jars with a paper towel in the ring instead of the metal circle. Or any plastic container that has holes punched in the top for air.
Then feed them everyday. Make sure they have plenty of food as once they get larger (like this one in the video) they really eat a lot! And they poop a lot too. So we clean their habitat out once a day. Once the swallowtail caterpillar starts to get big and fat, we put a stick in the container so that it can use it to support its chrysalis.
From hatching from its egg to entering its chrysalis, it is approximately 2 weeks. During this time it will molt, meaning it sheds it outer skin, several times. And it looks a bit more like the big one in the video each time.
Once it goes into its chrysalis, which can be either brown or green, it will take another 2 weeks or so before it emerges. Try not to disturb the "sleeping" caterpillar. Although if you handle it, the "tail" might wiggle a bit to try to scare you off.
Once the caterpillar has done his work inside its chrysalis, the chrysalis will start to turn transparent and split will appear on the top. It may take several days for the butterfly to work itself out of its chrysalis. Do not try to help the butterfly out in any way (we know from experience). Similar to a chick coming out of an egg, this is hard work that the butterfly must do on their own to build strength after its long "nap".
The butterfly will stick around for several minutes (we estimate from our experience about 20 minutes or so) while its wings dry. During this time, if you gently put your hand right in front of it, the butterfly usually climbs right onto your hand. Put it in a sunny spot on a flower or an orange cut in half while he rests.
It is always a sight to see them take off for the first time!
Have fun this summer with caterpillars!