Porterweeds

Porterweeds are a group of about 65 annual and perennial herbs and shrubs in the genus Stachytarpheta. The name derives from the Greek stachys (spike) and tarphys (thick) which refers to the thick flower spikes that produce blooms on these plants. Porterweeds are used as a medicinal plant in the Caribbean and one particular species is used to make a foaming brew that is used to reduce fevers. There are several varieties of Porterweed that can be found in the MOSI gardens.

Native Florida Jamacian Porterweed (Stachytarpheta jamaicensis) is a prostrate species that grows in low spreading mounds up to about a foot ro two feet in height. Although it is considered a Florida Native, Jamacian Porterweed was possibly brought over to Florida with early Bahamian settlers. Porterweeds are wonderfully attractive to butterflies as nectar plants and are an excellent addition to a butterfly garden. Jamacian Porterweed blooms throughout the year but may die back significantly during a freeze.

Blue Porterweed (Stachytarpheta cayennensis) syn (Stachytarpheta urticifolia) is an upright variety of porterweed that is also very attractive to butterflies. The plant may grow four to six feet in height and this species re-seeds readily, spreading rapidly. Blue Porterweed is a favorite of the Long Tailed Skipper butterfly which can often be found buzzing this plant in numbers. This variety is native to tropical areas of Asia and forms a woody shrub. This non-native variety has become a problem in some areas of Florida and has been listed as an invasive species. Identify this species as non-native by its height and deeply quilted leaves.

Pink Porterweed (Stachytarpheta mutabilis) is a variety that is native to South America but does very well in the climate of South Florida. In the Tampa Bay area this plant may struggle during colder months and can be killed back entirely by a freeze. The bright pink flowers of this Porterweed are striking but like the flowers of other Porterweed species, each flowers is very fleeting and last about a day on average. The flower-spikes produce flowers from the bottom up and keep blooming up the spike until the coldest parts of winter take hold.