Facts About Cloudless Sulphur Butterflies

Cloudless Sulphur butterflies are often overlooked. They’re medium-sized, common, and often too fast to get a good look at. They’re also easily confused with the Clouded Sulphur, which is extremely similar. With a little practice, though, you can learn to tell them apart.  Here are a few life facts about this pretty yellow butterfly, and how to attract it to your garden.

The Cloudless Sulphur (Phoebis sennae) is a member of the Pieridae family, which includes the even more common Cabbage White. Though they’re a more southern species, they usually spread north to cover most of the eastern U.S. in the summer months. In Florida and south Texas, they breed year-round. Their wings are a mostly uniform yellow, with some brown and white spots on females. Late summer Cloudless Sulphurs are often so pale as to appear white. Tell Cloudless Sulphurs apart from their look-alike, the Clouded Sulphur (Colius philodice), by their lack of black edging on the topsides of their wings. (Learn more here.)

Cloudless Sulphurs, like many other sulphurs, lay their eggs on members of the cassia family (Senna sp.). The eggs resemble a tiny grain of white or yellow rice, and are usually laid singly on the edges of leaves.

Cloudless Sulphur caterpillars are a bright green, with blue and/or yellow “racing stripes” down the side. If they eat the yellow flowers of the cassia plants they’re feeding on, they’ll often turn a gorgeous bright yellow instead.

The chrysalis of a Cloudless Sulphur has evolved to look like a leaf. It’s usually green, but can also be yellow or pink or a combination of the three. These pupa wiggle when touched, to scare off predators. As the butterfly inside develops, the outer skin of the chrysalis thins and the butterfly becomes visible beneath,

Attract these beautiful butterflies to your garden by planting their host plants, like partridge pea, Bahama cassia, wild senna, or other native species. Adults will feed on a wide variety of nectar plants, and their extra long proboscis means they’ll choose deep-throated flowers like petunias or honeysuckles that other butterflies may not be able to use. In the fall, Cloudless Sulphurs that have been living further north will head south before winter sets in, so add plenty of late-season nectar plants to your garden to help them on their way.