Rhododendron lepidotum

scaly rhododendron

Himalayan Asia — Nepal, Bhutan, Tibet, Sikkim, Yunnan; alpine and subalpine zones at 8,000-15,000 feet (2,400-4,600 m) elevation

At a Glance

TypeShrub
FoliageEvergreen
Height12-36 inches (30-90 cm)
Width18-36 inches (45-90 cm)
Maturity5 years

Growing Zones

USDA Hardiness Zones

5 - 8
These zones indicate the coldest temperatures this plant can typically survive.
What's my zone? →
Frost Tolerancehardy

Overview

Rhododendron lepidotum is scaly rhododendron, a compact mounding broadleaf evergreen shrub growing 12-36 inches (30-90 cm) tall and 18-36 inches (45-90 cm) wide. Small elliptic leaves 0.5-1.5 inches (1.3-4 cm) long, dark green above and brown-scaly (lepidote) beneath — the brown disc-shaped scales on the leaf undersides are visible under magnification. Terminal clusters of 3-6 tubular to funnel-shaped flowers 0.5-0.75 inch (1.3-2 cm), variable in color: pink, purple, yellow, or white depending on the wild population. In the heath family (Ericaceae). One of the smallest commonly cultivated Rhododendron species. Native to Himalayan alpine and subalpine zones at 8,000-15,000 feet (2,400-4,600 m). Requires acid soil pH 4.5-5.5 — chlorosis (yellowing between veins) develops in alkaline soils above pH 6.0. Does not tolerate sustained heat or drought — performs poorly in zones 8b and warmer, and requires consistent moisture in summer. All Rhododendron species contain grayanotoxins in leaves, flowers, nectar, and pollen — toxic to humans, pets, and livestock if ingested. Deer-resistant (toxicity). Zones 5-8. Part shade. Growth rate is slow.

Native Range

Native to Himalayan Asia — Nepal, Bhutan, Tibet, Sikkim, Yunnan — at alpine and subalpine elevations of 8,000-15,000 feet (2,400-4,600 m).

Suggested Uses

Grown in woodland gardens, rock gardens, and containers of at least 3 gallons (11 L) with acid potting mix. Alpine or Himalayan garden theme. Compact — 12-36 inches (30-90 cm). Acid soil required. Toxic — all parts. Deer-resistant. Zones 5-8.

How to Identify

Identified by small elliptic evergreen leaves 0.5-1.5 inches (1.3-4 cm) with brown disc-shaped scales (lepidote) on the undersides, on a compact mounding shrub. Terminal clusters of 3-6 tubular flowers (color variable). The small leaf size and the lepidote scales distinguish R. lepidotum from larger-leaved Rhododendron species. In Ericaceae.

Appearance

Size & Dimensions

Height1' - 3'
Width/Spread1'6" - 3'

Reaches mature size in approximately 5 years

Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~4 weeks
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Late spring to early summer (May-June). Terminal clusters of 3-6 tubular to funnel-shaped flowers 0.5-0.75 inch (1.3-2 cm), variable in color (pink, purple, yellow, or white). 4 weeks of bloom. Bee-pollinated.

Detailed Descriptions

Flower Description

Variable: pink, purple, yellow, or white depending on population; tubular to funnel-shaped, 0.5-0.75 inch (1.3-2 cm), in terminal clusters of 3-6

Foliage Description

Dark green above, brown-scaly (lepidote) beneath; small elliptic leaves 0.5-1.5 inches (1.3-4 cm) long; aromatic when bruised

Growing Conditions

Sun Requirements

Requires 3-6 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range4.5 - 5.5(Acidic)
357912
Soil Types
Drainagewell drained

Water & Climate

Water Needs

Medium

Frost Tolerance

hardy

Time to Maturity

3-5 years

Care & Maintenance

Care Guide

Part shade (3-6 hours). Acid soil pH 4.5-5.5 — chlorosis above pH 6.0. Well-drained but consistently moist. Mulch 2-3 inches (5-7 cm). Does not tolerate heat or drought — zones 5-8. All parts contain grayanotoxins — toxic. Deer-resistant. Slow growth.

Pruning

Remove spent flower clusters by snapping off at the truss base after bloom (June). Do not cut into old wood — Rhododendron does not regenerate from bare stems. Shape lightly if needed immediately after flowering.

Pruning Schedule

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summer

Maintenance Level

low

Container Growing

✓ Suitable for container growing

Minimum container size: 3 gallons

⚠️ Toxicity Warning

Toxic to pets and humans