Nature Space: Cheap & Easy Butterflies!

There are a lot places out there selling caterpillars for you and your young ones to rear and set free. Here’s a secret…you don’t need to buy caterpillars! Read on and learn how you can cecome the coolest parent on the block by raising your own caterpillars safely, easily, and cheaply!

What you’ll need:

• Wire mesh trashcan
• Piece of window screen that will cover the top of the trashcan with enough extra material to secure it
• Large rubber band or bungee cords to secure screen over can
• Glass or plastic 20oz bottle
• Water
• Empty butter container filled with soil
• A stick long enough to place in bottle so that 6-8 inches stick out the top

What you’ll do (and why):

• Find a caterpillar! Around your house, on a hiking trail, anywhere! It’s okay if you don’t know what kind of caterpillar it is. Caterpillars are almost always found on their host plant. This is the plant that they eat, because eating is just about all caterpillars do! Caterpillars are picky eaters, many times only eating one kind of plant. Many people fail at raising caterpillars because they try to feed them something other than their host plant. A caterpillar will die before trying a new food. I told you, they’re picky! You don’t have to know what the plant is that you find the caterpillar on, but you MUST know where to find more. You might want to flag the plant or tree to make it easy to find again.
• Clip the portion of the host plant with the caterpillar on it. Fill the bottle with water and put the end of the plant (the end without the caterpillar) down into the bottle. The bottle has a small enough mouth that the caterpillar should not fall in (they aren’t good swimmers).
  Place the bottle at the bottom of the mesh trash can. You now have a perfect caterpillar home. You just need to do a few more things if you want to see this guy (or girl) turn into a moth or butterfly.
• Place the stick in the bottle. Some caterpillars will want to make their chrysalis (moths make a cocoon, butterflies form a chrysalis) hanging off of a hard surface like a stick.
• Place the butter container filled with soil right next to the bottle on the bottom of the trash can. Some moth caterpillars like to pupate (turn into an adult) in soil, so it’s a good idea to have some there if you don’t know what kind of caterpillar you’ve found.
• Cover the trashcan with the window screen and secure it taught with a rubber band or bungee cord. There are several reasons for this. Caterpillars usually stay on their host plant until they are ready to pupate. If you want to watch them pupate, you better cover the top. Also, some caterpillars like to form their chrysalis hanging from the top. This is why a mesh trashcan is suggested. Other materials are often too slick for caterpillars to climb up. Finally, this will protect your caterpillars from predators.

Your butterfly emergence chamber is now complete!

A few more VERY IMPORTANT notes:

• Check the host plant food supply every day. Caterpillars eat a lot and have to keep eating if they are going to pupate. Always keep a fresh supply of food available.
• You should keep your butterfly cage in a sheltered area OUTSIDE. Temperature and day length help determine time of emergence for some moths and butterflies, so they must be exposed to these elements while pupating.
• What are all of those pellets at the bottom of your trashcan??? Caterpillars actually do one other thing besides eat! Their waste is called frass, and it must be dumped out of the can every few days.
• Check your cage every day when waiting for a butterfly to emerge. They will need to eat soon. When they emerge, they will need a few hours for their wings to dry. Many will hang from the top of the cage until they are ready to fly. Once they are ready to go, simply take the screen off the top and set your butterfly free!
• You and your kids will surely love this activity so much that you’ll want to do it over and over…great! Some caterpillars overwinter in their cocoon or chrysalis, so if you are collecting in the fall and a moth or butterfly does not emerge from pupation in a few weeks, it’s probably overwintering. If this is the case, be sure to use a plastic bottle to avoid water in glass bottles freezing and causing them to break (just learned this tidbit from personal experience last winter).
• If you have a cocoon in the soil, be sure to spritz it with water every week or so to keep it from drying out.

Benefits to the above method of caterpillar rearing:

• It’s cheap! You should spend no more than $10 on supplies.
• It’s easy!
• You reuse household items.
• You learn about the critters in your own environment.
• You are releasing butterflies and moths that are naturally found in your environment.
• You can raise lots of different kinds of caterpillars which is great for learning!

Helpful Caterpillar and Butterfly Resources:

Peterson First Guide to Caterpillars by Amy Bartlett Wright

Butterflies and Moths - A Golden Guide by Robert T. Mitchell and Herbert S. Zim