Coral Porterweed, Stachytarpheta mutabilis, is a large ornamental shrub from Central and South America. It is popular with gardeners due to its long floral spikes, covered in delicate, coral-colored flowers. It’s genus name, stachytarpheta, comes from the Greek words, “stachys”, meaning spike, and “tarphys”, meaning thick. This shrub is truly low maintenance! It can survive in most types of soil, will tolerate some shade, and once established, it has minimal watering needs. Best of all, it continuously produces flowers that contain copius amounts of nectar all day long, from spring through fall. This plant is an absolute butterfly and hummingbird magnet and is a staple of any butterfly garden.
Porterweeds are toxic, which offers them protection from many herbivores, so they really don’t have pest problems. In their native territory, however, they are the host plant for the tropical buckeye butterfly (Junonia evarete), which has evolved immunity to the plant’s chemical defenses, and figured out how to use those defenses for protection from their own predators.
(By guest contributor: Dany Millikin, Director of Education, Houston Botanic Garden)