Blooming for pollinators and growing for butterflies is Florida native Senna mexicana var. chapmanii (Chapman’s Wild Sensitive Plant; Bahama Senna). This shrub is endangered where it occurs naturally in the southernmost counties of Miami-Dade to the Monroe Keys in hammocks, pinelands and dunes. This plant can be grown further north of its range and is doing quite well here in our Sarasota County landscape. Bahama Senna grows quickly and reaches a height of 2-4 feet and is usually broader than tall with a spreading habit of 3-6 feet. The other commonly grown native Senna ligustrina (Privet Wild Sensitive Plant) has a more upright habit 4-8 feet tall and typically only 3-6 feet wide. We have had our Bahama Senna for about two years and it has remained around 2 feet tall and 3 feet wide. After established, Bahama Senna is drought tolerant and ours has survived on seasonal rainfall. Plant in full sun or light shade. Senna mexicana var. chapmanii is the larval host plant for Sulphur butterflies, including the Sleepy Orange, Cloudless Sulphur and the introduced Orange-barred Sulphur. Glands, called extralfloral nectaries at the base of the leaves attract ants that will attack the butterfly eggs and caterpillars. This protects the plant from defoliation by herbivores. This explains why not many of the caterpillars make it to adulthood in our garden. It might seem as though Mother Nature is playing a cruel joke, but this is not a big deal when we begin to realize that most of the critters that live in our garden serve a much bigger purpose than our superficial desire to choose one species over the other. We all need to eat!
*There are 11 Senna species that occur in Florida and only 4 of them are native to the state, Senna ligustrina (Privet Wild Sensitive Plant), Senna marilandica (Maryland Wild Sensitive Plant), Senna mexicana var. chapmanii (Chapman’s Wild Sensitive Plant; Bahama Senna) and Senna obtusifolia (Coffeeweed; Sicklepod). The two you can find available for sale at a Florida native plants nursery are S. ligustrina and S. mexicana var. chapmanii. See my previous article on S. ligustrina HERE. Be sure and avoid non-native Senna pendula var. glabrata (synonym Senna bicapsularis), a category I invasive in Florida. Common names for this invasive are Christmas Senna, Christmas Cassia and Climbing Cassia. When in doubt, always stick to our native species and Purchase your plants at a Florida native plants nursery affiliated with Florida Association of Native Nurseries. Find a native nursery in your neck of the woods by visiting Florida Association of Native Nurseries HERE.