Dog's Mercury Plant Care

Dog's Mercury (Mercurialis perennis) belongs to the Euphorbiaceae family within the Mercurialis genus. Dog's Mercury is native to much of Europe as well as in Algeria, Iran, Turkey, and the Caucasus. Dog's Mercury is also known as Perennial Mercury.

Dog's Mercury displays a low spreading groundcover growth habit, reaching up to 0.5 ft tall with a spread of approximately 1 ft. Dog's Mercury produces small inconspicuous flowers.

Leaf size: approximately 2 inches.

Water a young or newly planted Dog's Mercury 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.

Dog's Mercury thrives in partial to full shade. The optimal light range is 50–200 lux. Avoid placing Dog's Mercury in direct, harsh sunlight for extended periods, as this can scorch the foliage.

Mercurialis perennis tolerates temperatures of 60–75°F. Dog's Mercury prefers humidity levels of 40–60%.

Well-draining soil with high organic content. Good drainage is essential for Dog's Mercury to prevent waterlogging, which leads to root rot and fungal issues.

Feed Dog's Mercury every 8 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 partial to full shade and well-draining soil with high organic content. Avoid low spots where water collects after rain.

Dog's Mercury 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.

Dog's Mercury can spread to about 1 ft (0.3 m) and reach about 1 ft (0 m) tall. Space plants about 1 ft (0.3 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 Dog's Mercury 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.

Dog's Mercury 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.

Dog's Mercury can be propagated through seeds, stem cuttings. Similar propagation techniques also apply to annual mercury plant care, which shares the same genus.

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

Dog's Mercury 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.

Dog's Mercury grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Dog's Mercury is native to much of Europe as well as in Algeria, Iran, Turkey, and the Caucasus. In cooler regions, grow Dog's Mercury as a houseplant or bring it indoors before the first frost.