Monarch Butterflies: Chrysalis Watch

They really enjoy the goldenrod, but there are other nectar sources that they like as well, including the zinnias, coneflowers, Joe-Pye weed, liatris, bee balm, asters, phlox, mallows, mints, coreopsis, and rudbeckia.

Of course the buddleia, aptly nicknamed butterfly bush, is their favorite stop.

I am glad that we let stands of milkweed grow around our yard too. The flowers not only have a luscious scent, but they also attract lots of pollinating insects. Since they are the only plant monarch caterpillars feed on, the females lay their eggs here. The newly hatched larvae are ravenous eating machines and tear right into the milkweed leaves. Each female can lay up to 400 eggs!

Here are two tiny hatchlings on a milkweed leaf.

Milkweed is poisonous to most animals and a diet of it makes the monarch caterpillars distasteful to birds and other would-be predators, otherwise they would be readily picked off and eaten. Read more about milkweed.

As they eat and grow they outgrow their skins and shed them several times. Eventually the caterpillars get ready for their transformation into butterflies.

First they form a silken attachment and hang upside-down from it in a J shape.

Then they form a covering over themselves called a chrysalis. It is quite pretty, a light green with gold dots.

They can be hard to spot since the caterpillars will form them on the underside of a leaf or anything that will hold them.

We have found them on rocks, a garden bench, and even on a tomato!

The larvae pupate in here for about 2 weeks.

About 24 hours before the butterflies emerge, the shell of the chrysalis becomes clear enough to see the body of the adult butterfly and sometimes even the color patterns on their wings.

After breaking out of the chrysalis, they plump up their wings and dry them in the sun before flying off to tank up on nectar.

This generation of monarchs will not stay around to breed and lay more eggs. These guys have a long journey ahead of them and nectar is an essential fuel for their flight south. They will stop and refuel along the way, actually gaining weight during their flight south. This helps them survive the winter in semi-dormancy, high in the mountains of central Mexico.

Usually monarchs live only a few weeks but this migrating generation lives 8 or 9 months, long enough to make it to their wintering sites in Mexico and to head back northward in the spring.

It will take several generations before the monarchs make it all the way back to where I live in New England again but when they do we will be ready with lots for them to eat!

See the Almanac’s list of plants that attract butterflies.