Pussytoes and American Ladies in the Butterfly Garden

You might think it's all about the monarchs here at Our Little Acre, and it is, for the most part, but monarchs aren't the only butterflies that call our yard home. For several years now, we've monitored the reproduction of both Eastern black swallowtails and American ladies.

I raised this Eastern black swallowtail butterfly from a caterpillar in my house.

The Eastern black swallowtails are all over the bronze fennel we grow, for most of the summer, laying eggs, chowing down, and becoming adult butterflies. I've also found them on my carrot tops and when I grow parsley and dill, they make use of those plants, too.

The other butterfly that we see lay eggs here is the American lady (Vanessa cardui). It's often confused with the painted lady (Vanessa virginiensis) and it can be difficult to distinguish one from the other, especially when they're in flight.

If you can get close enough to see them with their wings open, the easiest way to tell the difference is to look for the presence of a tiny white spot on the upper wings. If it's there, you're looking at an American lady. If it's not, it's probably a painted lady. (I say probably, because apparently, now and then, American ladies are missing the dot, too.)  I've only ever seen American ladies here, although painted ladies are probably are probably present here as well.

In late April, I was doing some weeding in the garden and was witness to an American lady ovipositing (laying eggs) on my Antennaria plantaginifolia, more commonly known as pussytoes. I've grown this plant for years and unlike milkweed, I didn't plant it for the purpose of providing a host plant for butterflies. I just liked the name and the looks of the plant.

Antennaria is a bluish groundcover that throws up six-inch stems with small
clusters of flowers at the top. The flowers can be white or pink.

 

A female American lady butterfly laid eggs in the centers of two of the
fuzzy Antennaria leaves.

After the female lays an egg, a few days later, the tiny caterpillar will hatch out. It will use its spinneret to wrap itself up in a leaf with silk for protection when it isn't out and about, eating its host plant. This is usually the way you can know if there are caterpillars present, as they tend to only feed on cloudy days or at night.

Soon, you'll see larger caterpillars moving around on the leaves, still eating and preparing to pupate. I've never found a chrysalis in the garden, but they're masters at camouflaging them. Colors can vary from brown to green, according to their surroundings, and like the monarchs, they crawl away from their host plant to find a place to pupate.

Last year, I had Helichrysum petiolare 'Lemon Licorice' in my front flower boxes. American lady butterflies made use of that as a host plant too. Other plants they use include pearly everlasting (Anaphalis margaritacea), and some everlasting plants that are also known as cudweed (Gamochaeta spp.)