Hassall's polycarpaea Plant Care

Hassall's polycarpaea (Polycarpaea hassalensis) belongs to the Caryophyllaceae family within the Polycarpaea genus. Hassall's polycarpaea is native to the island of Abd al Kuri in Yemen's Socotra Archipelago. Hassall's polycarpaea is also known as Hassall's pimpernel.

Hassall's polycarpaea displays a low spreading ground cover growth habit, reaching up to 0.5 ft tall with a spread of approximately 1.5 ft. Hassall's polycarpaea produces small white or pink flowers in clusters.

Leaf size: approximately 1 inches.

Water a young or newly planted Hassall's polycarpaea 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.

Hassall's polycarpaea thrives in full sun to partial shade.

Polycarpaea hassalensis tolerates temperatures of 60–80°F. Hassall's polycarpaea prefers humidity levels of 40–60%.

Well-draining sandy soil mix with added organic matter. Good drainage is essential for Hassall's polycarpaea to prevent waterlogging, which leads to root rot and fungal issues.

Feed Hassall's polycarpaea every 6 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 sandy soil mix with added organic matter. Avoid low spots where water collects after rain.

Hassall's polycarpaea is suited to USDA Zone 11a – 12b.

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.

Hassall's polycarpaea can spread to about 2 ft (0.5 m) and reach about 1 ft (0 m) tall. Space plants about 2 ft (0.5 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 Hassall's polycarpaea 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.

Hassall's polycarpaea is frost-tender (hardy to USDA zone 11). In colder areas grow it in a container and move it to a bright, frost-free place before the first frost.

Hassall's polycarpaea can be propagated through seeds, division of root ball. Similar propagation techniques also apply to polycarpaea repens plant care, which shares the same genus.

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Hassall's polycarpaea 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.

Hassall's polycarpaea grows outdoors in USDA Zone 11a – 12b. It survives winters down to planting zone 11a. Hassall's polycarpaea is native to the island of Abd al Kuri in Yemen's Socotra Archipelago. In cooler regions, grow Hassall's polycarpaea as a houseplant or bring it indoors before the first frost.