- Division: Tracheophyta
- Class: Magnoliopsida
- Order: Lamiales
- Family: Verbenaceae
- Genus: Stachytarpheta
- Species: jamaicensis
Blue porterweed grows mostly in the tropical regions of the Americas, including the Caribbean. This dense, low-growing shrub grows in woodlands, savannas, scrub, and wetlands; and you’ll often find it sprawling along the coast and beside roadsides. When stems reach about four feet tall, they droop toward the ground. An evergreen perennial that blooms nearly year-round in many places, its blue flowers attract bees and butterflies. A host plant for the tropical buckeye, blue porterweed also attracts large orange sulphurs, clouded skippers, gulf fritillaries, red admirals, and julias.
Long, swirly spikes bear small, showy, bluish or purplish flowers. Each flower stays open for just a day or so, but new flowers—on the same spike—open every few days. As blue porterweed grows large, its stems turn woody toward the base. Its small, dark green leaves have toothed edges.
Sand, clay or loam? This adaptable shrub will do fine in any soil that drains well—even lime rock. Give it partial shade or full sun, and don’t overwater it. Once established, blue porterweed is quite drought tolerant. It’s a great choice for a butterfly garden, meadow, ground cover, or in a hanging basket or other container.
We don’t recommend it, but blue porterweed is reported to have a wide range of medicinal uses, from treating fungal infections to high blood pressure, colds, constipation, diarrhea, boils, burns, earache, headache, allergies, worms, and “nervous pains.”