Hoary Rockrose Plant Care

Hoary Rockrose (Helianthemum canum) belongs to the Cistaceae family within the Helianthemum genus. Hoary Rockrose is also known as Hoary Sunrose.

Hoary Rockrose displays a low spreading ground cover growth habit, reaching up to 0.5 ft tall with a spread of approximately 1.5 ft. Hoary Rockrose produces showy, saucer-shaped flowers in various colors.

Leaf size: approximately 1 inches.

Water a young or newly planted Hoary Rockrose 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.

Hoary Rockrose thrives in full sun to partial shade.

Helianthemum canum tolerates temperatures of 50–80°F. Hoary Rockrose prefers humidity levels of 30–60%.

Well-draining sandy soil with added organic matter for nutrients. Good drainage is essential for Hoary Rockrose to prevent waterlogging, which leads to root rot and fungal issues.

Feed Hoary Rockrose 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 with added organic matter for nutrients. Avoid low spots where water collects after rain.

Hoary Rockrose is suited to USDA Zone 12a.

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.

Hoary Rockrose 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 Hoary Rockrose 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.

Hoary Rockrose is frost-tender (hardy to USDA zone 12). In colder areas grow it in a container and move it to a bright, frost-free place before the first frost.

Hoary Rockrose can be propagated through seeds, softwood cuttings. Similar propagation techniques also apply to apennine rockrose plant care, which shares the same genus.

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

Hoary Rockrose is susceptible to aphids, spider mites. 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.

Hoary Rockrose grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. In cooler regions, grow Hoary Rockrose as a houseplant or bring it indoors before the first frost.