Prickly Oplonia Plant Care

Prickly Oplonia (Oplonia spinosa) belongs to the Acanthaceae family within the Oplonia genus. Prickly Oplonia is native to several Caribbean islands. Prickly Oplonia is also known as Spiny Oplonia.

Prickly Oplonia displays a low rosette, clumping growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Prickly Oplonia produces small tubular flowers in shades of pink, purple, or white.

Leaf size: approximately 4 inches.

Water a young or newly planted Prickly Oplonia every 7–14 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.

Prickly Oplonia thrives in bright indirect light. Avoid placing Prickly Oplonia in direct, harsh sunlight for extended periods, as this can scorch the foliage.

Oplonia spinosa tolerates temperatures of 65–80°F. Prickly Oplonia prefers humidity levels of 40–60%.

Well-draining sandy loam with added organic matter for moisture retention. Good drainage is essential for Prickly Oplonia to prevent waterlogging, which leads to root rot and fungal issues.

Feed Prickly Oplonia every month 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 bright indirect light and well-draining sandy loam with added organic matter for moisture retention. Avoid low spots where water collects after rain.

Prickly Oplonia is suited to USDA Zone 10b – 11b.

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.

Prickly Oplonia 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 Prickly Oplonia 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.

Prickly Oplonia is frost-tender (hardy to USDA zone 10). In colder areas grow it in a container and move it to a bright, frost-free place before the first frost.

Prickly Oplonia can be propagated through stem cuttings, division of offsets.

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

Prickly Oplonia is susceptible to aphids, spider mites, mealybugs. 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.

Prickly Oplonia grows outdoors in USDA Zone 10b – 11b. It survives winters down to planting zone 10b. Prickly Oplonia is native to several Caribbean islands. In cooler regions, grow Prickly Oplonia as a houseplant or bring it indoors before the first frost.