A great project to teach children to protect and respect nature and to give them a bit of perspective on their own life is to allow them to watch caterpillars turn into butterflies. We have a safe way to do this, without harming the caterpillars or butterflies.
Once you have created a successful butterfly garden,for this project, be sure to plant a few of the smaller host plants (like Asclepias) in smaller pots which you can move and remove easy within your butterfly garden. Once your plants are fairly established and beginning to flower, you can begin the first stage of this project.
Watch closely for butterflies to become interested in these host plants. Remember, butterflies do not feed from the host plants, they lay their eggs on them and caterpillars feed from them. You may notice butterflies landing on the host plants and staying for a moment or two. They are, most likely, laying their eggs. Once you see this happen, watch for caterpillars to begin to emerge in a few days (3-5 days, usually).
You will know caterpillars have emerged when you begin to see your host plants begin munched on. Leave them undisturbed until they begin to get fat (fatter than the width of an average pencil and longer than 2 inches) which usually takes about a week and a half. Once they get big enough, take a leaf and gently transfer them from the plant they are on to one of your potted host plants.
Then, take a square of fine wire netting (or screen) a few inches taller than the plant and pot combined but no wider than the top of the pot (the area of soil) and roll it to create a cone shape. Take some bread twist ties (or soft wire) and secure the shape.
Cut the bottom of the wire cone (the large end NOT the small end) so that you can fit it tightly in the soil near the edges of the pot and then simply cover the plant with the caterpillar with the cone and secure it by twisting the cone slightly into the soil.
Put the pot with the cone over it in a shaded area where it is easily visible by you and your child but still remains mainly undisturbed and comfortable. As well, do not put it them in a high traffic area or where sounds or vibrations may disturb it. A nice quiet place is the best place to watch your caterpillar turn into a butterfly.
Soon, your caterpillar will begin to attach to either the plant or the screen and hang upside down, preparing for the big change. Within the next 24 hours, the caterpillar will be secure in the chrysalis stage for about ten days.
The chrysalis stays about the same for about a week and there is really not much to see, at this point. During this time, you will want to open up your cone in preparation for a better view and release of your butterfly. You can do this by either opening up your twist ties or cutting the screen to open it. Be sure to be very careful, to keep from disturbing the chrysalis, remember that your future butterfly is alive and growing, at this stage.
After about a week, the color of the chrysalis will turn dark. Then, in the next couple of days, you may begin to see a bit of murky color from the butterfly wings. When this happens, watch closely because you may have a butterfly within the day or even a couple of hours.
As the butterfly emerges, you will begin to see movement. The chrysalis will break open and a butterfly will emerge. However, it takes some time for the butterfly to get its blood pumping enough to fly away so you will have some time to watch the transformation which is quite incredible. Once your butterfly flies away, don’t worry, if you have provided an adequate food supply in your garden, it will be back.