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Rhododendron 'H.H. Hume'

Image of Rhododendron 'H.H. Hume'

James Burghardt

Family

Ericaceae

Botanical Name

Rhododendron 'H.H. Hume'

Plant Common Name

Evergreen Azalea, H.H. Hume Azalea

General Description

The large double white flowers of this Beltsville evergreen azalea are borne in clusters in early to mid-spring. The wavy-edged, yellowish-throated blooms are hose-in-hose (with two "stacked" whorls of petals). This chest-high shrub has elliptic olive-green leaves.

The Beltsville Hybrid azaleas were developed in the late 1950s by Guy E. Yerkes and Robert L. Pryor of the United States Department of Agriculture’s Beltsville, Maryland, Station. They are complex Rhododendron hybrids involving several species and cultivars. They were intended for both greenhouse and landscape use.

Like most azaleas, this cultivar prefers partial shade and highly organic acid soil that is evenly moist but well-drained. Plant it shallowly and mulch with pine needles, bark mulch, or other organic material to conserve moisture and suppress weeds. It does best in warm summers but requires some winter cold for good growth. Do any necessary pruning directly after the flowers fade, before next year's buds form. Try to site it where it will not need to be pruned back.

Providing provide the perfect backdrop for almost any spring-blooming bulb or perennial, the Beltsville Hybrids are popular for containers, Japanese gardens, and mixed borders.

Characteristics

  • AHS Heat Zone

    9 - 1

  • USDA Hardiness Zone

    7 - 9

  • Sunset Zone

    5, 6, 7, 8, 9, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24

  • Plant Type

    Broadleaf Evergreen

  • Sun Exposure

    Partial Sun, Partial Shade

  • Height

    4'-6' / 1.2m - 1.8m

  • Width

    4'-6' / 1.2m - 1.8m

  • Bloom Time

    Spring

  • Native To

    Hybrid Origin

Growing Conditions

  • Soil pH

    Acidic

  • Soil Drainage

    Well Drained

  • Soil type

    Loam, Sand

  • Growth Rate

    Medium

  • Water Requirements

    Average Water

  • Habit

    Oval/Rounded

  • Seasonal Interest

    Spring, Summer, Fall, Winter

Ornamental Features

  • Flower Interest

    Showy

  • Flower Color

    White, Light Yellow

  • Fruit Color

    Green, Tan

  • Foliage Color (Spring)

    Green

  • Foliage Color (Summer)

    Green

  • Foliage Color (Fall)

    Green

  • Foliage Color (Winter)

    Green

  • Bark Color

    Brown, Gray

  • Fragrant Flowers

    No

  • Fragrant Fruit

    No

  • Fragrant Foliage

    No

  • Bark or Stem Fragrant

    No

  • Flower Petal Number

    Double

  • Repeat Bloomer

    No

  • Showy Fruit

    No

  • Edible Fruit

    No

  • Showy Foliage

    No

  • Foliage Texture

    Medium

  • Foliage Sheen

    Matte

  • Evergreen

    Yes

  • Showy Bark

    No

Special Characteristics

  • Bark Texture

    Smooth

  • Usage

    Container, Feature Plant, Foundation, Hedges, Mixed Border, Topiary / Bonsai / Espalier

  • Sharp or Has Thorns

    No

  • Invasive

    No

  • Self-Sowing

    No