A friend recently posted on FB that she'd brought in three swallowtail caterpillars and her family was watching them go through the incredible process of metamorphosis to become butterflies. Her post reminded me of the times I've done this with my children, back in the day when all three were younger and still at home. We've been successful twice, with monarch caterpillars both times!
Here are a few posts from my former blog describing the process:
Meet Tony and Bella.
They've done it!
I'm sure you can find a lot of info online about doing this, or in a book you have already sitting on your shelves (this is a great one).
It's not all that complicated really -- the main thing is to observe the plant that the caterpillar is on before you bring it in the house -- that will tell you what food to provide for your temporary resident. Our monarchs were happily munching away on my butterfly weed (also known as "orange glory flower" or asclepias tuberosa) which is a type of milkweed. As you probably know, caterpillars love milkweed.
Find yourself an unused, clean jar (mason, mayonnaise, spaghetti sauce, etc.) with a tight-fitting lid and put your new friend in it with a handful of leaves and a stick or two for it to crawl on and eventually make it's chrysalis on. (Although actually in the case pictured here, the caterpillar attached itself to the underneath of the jar lid!) Punch a few holes in the lid for airflow. And of course you'll need to replenish the food every day or whenever the caterpillar eats what you put in the jar.
The only sorta gross part of this process is that your caterpillar will do a lot of going-to-the-bathroom and it will all fall to the bottom of the jar. It's basically a poop-making machine for the next little while...
It could take a few days or longer for the chrysalis to form -- it all depends on how long into the process your little friend was before you adopted him or her. In this case pictured here it was only 2 days from when we put the first caterpillar into the jar to when the chrysalis was formed! The part where they go from caterpillar-clinging-to-a-stick to shiny green chrysalis is soo cool! Hopefully you can actually watch that part.
The butterfly will emerge in 10-14 days. Put the jar outside when the chrysalis breaks open and watch the miracle occur!
It may be a bit late for all of you for this year-- but keep this idea in mind for next year!
And if you can't find a caterpillar in your own backyard, here is a place where you can order a "butterfly rearing" kit online.