Among all the species in the Cassia/Senna group, Senna mexicana is one of the most desirable to grow. It flowers nearly continuously throughout the year, providing plenty of color in the landscape. It also generally grows no more than 3 to 4 feet tall, making it easier to manage in small landscapes and butterfly gardens.
Yes, this is a great butterfly plant, serving as a larval food plant for the Cloudless Sulphur, Orange-barred Sulphur, and Sleepy Orange butterflies.
Senna mexicana is native to Central and South America, the Caribbean, and South Florida.
It is recommended for USDA Zones 9b - 11, but stays small enough to be container-grown anywhere.
It will grow in full sun to light shade. Although flowering is probably best in full sun, mine bloom well with only a couple of hours of late-afternoon sunlight.
The evergreen leaves are alternate and pinnate. Flowers are followed by flat, dry pods that turn brown when mature.
Established plants are drought-tolerant, and they are also salt-tolerant, making this a good choice for coastal plantings.
Propagation is usually by seed.