One of the most often-viewed butterflies in Texas is the Sulphur Butterfly. Even if you haven’t seen any Monarchs, Swallowtails, Pipevines or Zebras you are sure to have seen the sulphurs. When first viewed by observers, this species of butterfly was referred to as having a buttery coloration. In fact, it is believed that this is how these fluttering insects got the name of “butterfly.”
In the springtime, if you drive up to the hill country to view the bluebonnets, it is likely you will also encounter the sulphurs ”puddling” in water puddles next to the side of asphalt roads. This is their way of drinking in necessary nutrients that are made available to them through salts and minerals derived from the soil. Sulphur butterflies often have solid yellow wing colorations that may be mottled with orange, lime-green, rusty amber, soft brown or grey spots.
Within the confines of the Cockrell Butterfly Center Demonstration Garden (located outside the conservatory), we have two host plants available for the sulphur butterflies to lay eggs upon – the Cassia alata and the Cassia bicapsularis. If you’re interested in the early stages of the butterfly’s life cycle, these two plants always have eggs and caterpillars on them. Be aware that wasps, a predator of the larvae, can sometimes be seen carrying them off as food.
The Cassia alatas are grown in our greenhouses with seeds collected from specimens that formed pods after flowering the previous fall. We scarify (by making a tiny cut in the seed coat) and then soak them in water for 24 hours before planting them into flats in the month of December.
By April (when they are available at the Spring Plant Sale), the plants are in one gallon pots and are over 24” tall. In maturity, the Cassia alata can reach 8 to 10 feet or more in height.
The blooms atop the Cassia alata are on top of tall erect stems that are about 6-8” in length and look like yellow candles from a distance – which is why gardeners refer to them as the “candlestick cassia.” The plant does well in full sun, but may freeze back in the winter. It does not always come back with shoots in the spring.
The Cassia bicapsularis is a slower-growing shrub with tiny leaves sitting opposite one another on slender branches. The blooms on the bicapsularis are softer, single, and drape downward as they cascade over the end tips of the stems. They are a beautiful sight in full bloom. In our garden at the Cockrell Butterfly Center, I have noticed that Orange Barred Sulphur Butterflies prefer the bicapsularis while the Cloudless Sulphurs prefer the alata. This flowering shrub is a little gem and certain to enhance your garden from one season to the next:
The eggs of sulphur butterflies are laid singly and look like small pieces of thread to the naked eye. They are generally laid on the tips of new leaf growth. The larvae of the sulphurs come in all shades of green and yellow. Some are solid in coloration and some carry spots or stripes. They are well camouflaged among the green leaf structures and the yellow blooms. The chrysalis attaches itself to a surface with two silk girdles and has a curvaceous shape.
If you want to view these butterflies and learn more about them, consider purchasing the book The Butterflies of Houston and Southeast Texas by John and Gloria Tveten. This book is an exceptional reference guide with photographs of the butterflies, caterpillar and notes on the nectar and host plants of each specific species. The book is listed on the back of our Butterfly Gardening Brochure.
Want to learn more about Horticulture and butterflies?
Learn what the Black Swallowtail likes to eat.
What attracts Monarchs to your garden?
Where do they grow all those plants? Discover the greenhouses here at the HMNS.