Rabbitbells (Crotalaria rotundifolia) is a small herbaceous wildflower that is quite common throughout the state of Florida. This native perennial has stems that spread over the ground, reaching a height of a few inches. The small bright yellow flowers form on short stalks about 3 to 6 inches long. Look for this plant in sunny, sandy areas, such as sandhills, pinelands, sandy roadsides and disturbed areas.
The simple leaves are oval or elliptic in shape, averaging about 3/4-inch in length. They are attached alternately to the stem. The stem and one side of the leaves are covered with short hairs.
The small yellow flowers are about a half-inch long. They are pea-shaped, having a broadly rounded banner petal, two narrow wing petals, and a curved keel. In southern Florida, these flowers bloom year round.
The flowers produce inflated cylindrical seed pods about 1 inch long. They are green in color, eventually turning brown at maturity.
Another name commonly used for rabbitbells is prostrate rattlebox because of the plant’s creeping nature. Most of the common names of the Crotalaria species include the word rattlebox. This is due to the fact that when the seeds in the pod become loose, they make a rattling noise when shaken.
In Florida, 15 species of the Crotalaria genus have been documented by the University of South Florida in its Atlas of Florida Plants (Florida.PlantAtlas.usf.edu). Of these, only four are considered native species.
A characteristic of the Crotalaria species, including rabbitbells, is that they contain pyrrolizidine alkaloids that render the entire plant (especially the seeds) poisonous. These plants should not be eaten by livestock or other animals such as your pets.
Although these plants are poisonous to animals, it serves as a host plant for the ceraunus blue butterfly and the rattlebox moth, aka bella moth — one of the more brightly colored day-flying moths seen in Florida. It depends on the chemicals produced by the Crotalaria species for its bright colors. The larvae of this moth penetrate the seed pods and eat the seeds, thus helping to control the spread of this poisonous plant.
Be sure to take time to walk through your neighborhood and look for the rabbitbells plant, which is now in bloom. All of the photographs accompanying this article were taken by the author in the Deep Creek neighborhood.