About a week ago, I found a Black Swallowtail egg on my dill. A couple of days ago, I found this wee little 1st instar caterpillar chowing down on my dill. He's very tiny, probably about 1/4" long. I knew that I'd need to get some butterfly cages ready to keep some of these inside and away from predators, such as wasps, if I was to help the butterfly population.
Not only are butterflies pretty to look at, they are important pollinators. Some species, like the beautiful Monarch butterfly, are in danger due to their food source being taken out by pesticide use, urban sprawl, and drought. I'm not a huge butterfly lover, but I do try to plant butterfly friendly plants, not necessarily to attract them to my garden, but to help them along in their journey and reproduction cycle.
Several years ago, I planted some dill in my garden for my husband. He has a life-long goal of making dill pickles using fresh dill, dill seeds, and cucumbers from our garden. I freaked out when I saw a huge caterpillar destroying "his" dill! I immediately snapped a picture of it and posted it on
my favorite gardening website to find out what it was and if was friend or foe. I was quickly informed it was an
Eastern Black Swallowtail. It's a keeper and should be "protected", raised away from harm, and then released. I grabbed a plastic container, an old medicine bottle that I'd washed out, a paper towel, some dill, and some orange tulle and began my butterfly cage journey. Over the years, I've redesigned my cage with the help of a couple of fellow gardening buddies. If you'd like to make your own butterfly cage (or caterpillar cage), they are inexpensive and easy to make.
What you'll need:
- Floral Foam or floral clay (I prefer the foam)
- Scissors
- Glad Press 'n Seal cling wrap
- Scissors
- Box opener
- Deep food storage container (approx. 64 oz)
- Tulle (Wedding netting)
- Water bottle, if using floral clay
- Hot glue gun
- A nosy kitty is a nice accessory and helper (NOT!)
** I buy my food storage containers from Family Dollar, similar to
this one from Glad.. Be sure to get the deep rectangular ones so your caterpillars will have enough room in the container with your host plant.
First off, using your box cutter/box opener/razor blade, cut out the center of the lid. Leave enough space to put a bead of glue around the edge without getting into the grove for the lid to snap onto the bottom. This one is actually cut a little too close to the edge, but I went with it anyway. Then, cut your tulle approximately 2" -3" larger than your lid. I just lay the lid on the tulle and start cutting. No measuring required!
Using your hot glue gun, run a bead of glue around the cut edge. Place your tulle on top and press down. You can use a popsicle stick or orange stick to press it down. If you like to burn your fingers, you can just use your fingers. I'm really not into that, so I used a popsicle stick.
While the glue job is drying, cut your floral foam to fit the bottom of your cage. You're going to set your cage on its end, so make sure your piece fits. You can use one side of the scissors as a knife to cut your foam. I like it to be about 2" deep so it has enough room to hold the stems of the plants.
Tear off a piece of the Glad Press 'n Seal wrap large enough to wrap your piece of floral foam. I dare you to do this without trying to kill yourself on the cutter on the box. If you're really lucky, the cutter on the box won't even work! (Not fun!)
Wrap it all up nice and neat. Make sure it's nice and tight. The reason I wrap my piece of floral foam is to make clean up of the cage quicker and easier. Caterpillars create an enormous amount of frass (aka "poop") and the wrap keeps the frass from contaminating the foam. It wipes off easily and quickly to make daily cleaning quick.
* If you're using floral clay, cut the bottom of your water bottle off,
about 1" - 1.5" from the bottom with your box opener or scissors. Fill
with clay and wrap the foam and bottom of the water bottle with the
plastic wrap. Poke some holes in the wrap and clay, wet, and then place
your sprigs of host plant in the clay.
Using a toothpick, poke some holes into the foam. I like to wiggle the toothpick around a bit to make holes large enough for the stems. Make several different sizes to accommodate the possible various stem sizes. If you don't have a caterpillar ready to move it, place the foam in the cage and place the lid on top and store it for when you need it. If you've got a resident ready to move in, continue reading.
Place your square of foam into some water. It'll float, so you'll need to place something on top of it to hold it down. A cat food dish worked great for me. Allow it to soak while you collect your host plant stems and occupant, if you've not already brought them inside. I had an Eastern Black Swallowtail caterpillar waiting, so I went and collected several sprigs of dill and the little caterpillar.
Once your foam is watered and full (it turns a dark green), place it on a paper towel in the bottom of your cage. The paper towel also helps ease cleaning.
Prior to placing your resident and sprigs of host plant into your cage, be sure to rinse off, upside down, in some slow running water. This helps rinse of any predators or other buggies that might attack the caterpillar. Once the sprigs are rinsed off, gently place them into the holes in the foam.
Snap your lid on and move your cage to a safe place. You want it in a sunny location, but not in direct sun. I use a rubber band around the cage not only to keep the lid on securely, but also to help keep my inquisitive cats out of the cage. They don't normally bother the cages, but I don't want to take any chances.
There you have it! Very easy to do and the clear container makes it easy to see what's going on inside. It also provides easy clean up once you release your butterfly. These are easy to store and last for several years. If you have kids, they can decorate the outside with paint or stickers to personalize them.
A few tips:
- Be sure to change the paper towel daily and clean out any frass on the foam.
- I can usually change out the food source every other day.
- I also keep a spare piece of foam wrapped up to use when I change out the food source.
- To transfer the caterpillar to the new sprigs of food, just lay the sprig it's on in the mess of the new sprigs. It'll figure out how to get onto the new stuff.
- Learn the stages of your caterpillar's growth. When it gets to the advanced stages, but before it pupates (eliminates all waste from its body, goes into the "comma" position, and starts making its chrysalis), put a larger twig or small stick in the cage. It will use that to build its chrysalis on and won't need any food source.
