Cayenne Porterweed Plant Care

Cayenne Porterweed (Stachytarpheta cayennensis) belongs to the Verbenaceae family within the Stachytarpheta genus. Cayenne Porterweed is native to the Americas, from Mexico south through Central and South America to Argentina, as well as many islands of the Caribbean. Cayenne Porterweed is also known as Blue Porterweed, Snakeweed, Dwarf Porterweed.

Cayenne Porterweed displays an upright, bushy shrub growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Cayenne Porterweed produces tall spikes of tubular flowers in shades of blue, purple, or white.

Leaf size: approximately 6 inches.

Water a young or newly planted Cayenne Porterweed every 7–10 days, soaking the whole root zone, until it is established — usually one to two growing seasons. Established shrubs mainly need water during long dry spells. In a container, water whenever the top few centimetres of soil are dry.

Cayenne Porterweed thrives in full sun to partial shade.

Stachytarpheta cayennensis tolerates temperatures of 60–85°F. Cayenne Porterweed prefers humidity levels of 40–70%.

Well-draining, fertile soil with added organic matter. Good drainage is essential for Cayenne Porterweed to prevent waterlogging, which leads to root rot and fungal issues.

Feed Cayenne Porterweed every 4 months during the growing season with a balanced, slow-release fertilizer at the rate on the label. Established shrubs in good soil often need little extra feeding, so let weak growth or pale foliage guide you.

Stop feeding by late summer so new growth can harden before winter.

The PlantoScan app can remind you when to water and when to fertilize each plant.

Choose a spot with full sun to partial shade and well-draining, fertile soil with added organic matter. Avoid low spots where water collects after rain.

Cayenne Porterweed is suited to USDA Zone 13a.

Plant container-grown or balled-and-burlapped shrubs in spring or early autumn, setting the root flare at soil level, and water well after planting.

Cayenne Porterweed can spread to about 2 ft (0.6 m) and reach about 3 ft (1 m) tall. Space plants about 2 ft (0.6 m) apart so mature crowns don't crowd each other, and plant at least half that distance from buildings, fences and paths.

Planning a row or hedge? Try the plant spacing calculator.

Prune Cayenne Porterweed while it is dormant in late winter: first remove dead, damaged and crossing branches, then thin lightly for shape.

If it flowers in spring, prune right after flowering instead so you don't remove next year's buds. Never take off more than about a quarter of the shrub in one year.

Cayenne Porterweed is frost-tender (hardy to USDA zone 13). In colder areas grow it in a container and move it to a bright, frost-free place before the first frost.

Cayenne Porterweed can be propagated through stem cuttings, division. Similar propagation techniques also apply to indian porterweed plant care, which shares the same genus.

See all plants toxic to cats and plants toxic to dogs.

Cayenne Porterweed is susceptible to aphids, spider mites, whiteflies. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.

Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.

Cayenne Porterweed grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Cayenne Porterweed is native to the Americas, from Mexico south through Central and South America to Argentina, as well as many islands of the Caribbean. In cooler regions, grow Cayenne Porterweed as a houseplant or bring it indoors before the first frost.