Ledum maximum Plant Care

Ledum maximum (Nakai) A.P.Khokhr. & Mazurenko

Updated · Sources · How we source care data

Rhododendron tomentosum, commonly known as marsh Labrador tea, northern Labrador tea, marsh rosemary or wild rosemary, is a flowering plant in the subsection Ledum of the large genus Rhododendron in the family Ericaceae.

🌿Shrubs
Water

Every 7–10 days

Light

Partial shade to full sun

Temp

50–75°F

Humidity

40–60%

At a glance

How do you care for Ledum maximum?

Plant Ledum maximum in partial shade to full sun (USDA zones 12a) and water a young shrub every 7–10 days until it is established. It tolerates temperatures of 50–75°F (10–24°C). Fertilize it every 6 months during the growing season.

What Is the Ledum maximum?

Ledum maximum (Ledum maximum) belongs to the Ericaceae family within the Ledum genus.

Ledum maximum displays an upright, dense shrub growth habit, reaching up to 4 ft tall with a spread of approximately 3 ft. Ledum maximum produces small white or pink flowers in dense clusters.

Leaf size: approximately 1.5 inches.

How Often Should You Water a Ledum maximum?

Water a young or newly planted Ledum maximum 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.

Watering Frequency

Every 7–10 days

Until established; then in dry spells

What Light Does the Ledum maximum Need?

Ledum maximum thrives in partial shade to full sun.

Light Requirement

Partial shade to full sun

What Temperature and Humidity Does the Ledum maximum Prefer?

Ledum maximum tolerates temperatures of 50–75°F. Ledum maximum prefers humidity levels of 40–60%.

Temperature

50–75°F

Humidity

40–60%

What Soil Mix Works Best for a Ledum maximum?

Moist, acidic, well-draining soil with high organic matter content. Good drainage is essential for Ledum maximum to prevent waterlogging, which leads to root rot and fungal issues.

How Often Should You Fertilize a Ledum maximum?

Feed Ledum maximum 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.

Fertilizing

Every 6 months

During the growing season

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

Where Should You Plant a Ledum maximum?

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

Ledum maximum 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.

How Far Apart Should You Plant a Ledum maximum?

Ledum maximum can spread to about 3 ft (0.9 m) and reach about 4 ft (1 m) tall. Space plants about 3 ft (0.9 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.

How Do You Prune a Ledum maximum?

Prune Ledum maximum 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.

How Do You Care for a Ledum maximum in Winter?

Ledum maximum 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.

How Do You Propagate a Ledum maximum?

Ledum maximum can be propagated through softwood cuttings, layering, division.

Is the Ledum maximum Toxic to Pets and Children?

Pet safety not verified

The ASPCA does not list Ledum maximum, so we can't confirm whether it is safe for cats and dogs. Keep pets from chewing it as a precaution.

This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.

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

What Pests and Diseases Affect the Ledum maximum?

Ledum maximum is susceptible to spider mites, lace bugs, scale insects. 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.

What USDA Hardiness Zone Does the Ledum maximum Need?

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

Hardiness Zone

Zone 12a

Keep exploring plants

Ledum maximum is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.

It belongs to the Ledum genus (family Ericaceae) — search all Ledum species in the plant lookup.

Ledum maximum thrives in bright light and direct sun — see other bright-light plants.

Related Plant Care Guides

Closely related plants with similar care requirements:

Sources

  • Scientific name & taxonomy: Ledum maximum (Nakai) A.P.Khokhr. & Mazurenko, family Ericaceae (first published in Sosud. Rast. Sovet. Dal'nego Vostoka 5: 122 (1991)) — World Flora Online record, IPNI name record.
  • Pet toxicity: Pet safety not verified: the ASPCA does not list Ledum maximum, so we can't confirm whether it is safe for cats and dogs. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
  • Hardiness zone: USDA Zone 12a, calculated from the plant's minimum temperature.
  • Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.

Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.

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