Photo of Irene Koster Azalea flower by Briggs Plant Propagators

Photo by Briggs Plant Propagators

Used with permission, all rights reserved

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Buy Irene Koster Azalea

Scientific Name: Rhododendron 'Irene Koster'

Also Known As

  • Azalea 'Irene Koster'
  • Irene Koster Deciduous Azalea

Plant type

shrub

size

  • H: 6'-8'
  • W: 4'-6'

planting zones

  • 5a-9b

8-12 inch | $34.75

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Fewer than 10 at Bloom River Gardens

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Irene Koster Azalea plant details

Irene Koster Azalea is a broadleaf deciduous shrub with green foliage. In spring pink flowers emerge. Features glossy texture. Attracts bees, beneficial insects, butterflies and hummingbirds making it an excellent addition to pollinator gardens. Grows well with mostly sun - mostly shade and even moisture - regular water. Does well in acidic, rich and well-drained soil. A good option if you're seeking something verticillium wilt resistant.

CHARACTERISTICS OF Irene Koster Azalea

Plant type: shrub
Plant family: ericaceae
Foliage: deciduous green
Mature size: 4 FT - 6 FT - wide, 6 FT - 8 FT - tall
Flowers: pink blooms in spring
Uses: border plant, container plant, fall color, fragrant, woodland garden

GROWING CONDITIONS for Irene Koster Azalea

USDA Zones: 5a - 9b
Sun exposure: mostly sun - mostly shade
Watering frequency: even moisture - regular
Resistant to: verticillium wilt
Soil needs: acidic, rich and well-drained

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Nursery contributed plant descriptions

Prominent buds with attractive stripes of pink open to reveal pale rose-pink flowers with a golden-yellow flair. Deliciously fragrant. Twiggy deciduous shrub. Grow in evenly moist, well drained acidic soils in full to filtered sun. Hardy to at least -25 °F.
Fragrant, white flowers with pink stripes and yellow flare, shiny green foliage turns orange-red in fall Zones 7-9.
Beautiful, later blooming, light rose-pink flowers have a showy yellow-gold flare on the upper petals. The buds are especially attractive with stripes of pink that run their length, providing contrast to the open flowers. Growth habit is a little broader and less tall than many deciduous azaleas. But the best part is a very sweet scent! Wow! FRAGRANT

By: Greer Gardens Inc.

Fragrant, 2-3" blush-pink blooms appear in late midseason. AGM winner.

Gardening facts about Irene Koster Azalea plant

How to Grow Irene Koster Azalea

  • Sun Exposure

    • mostly sun - mostly shade
  • Water Needs

    • even moisture - regular
  • Soil Needs

    • acidic
    • well-drained
    • rich
  • Special Situation

    • verticillium wilt resistant

Features

  • Foliage Color

    • green
  • Flower Color

    • pink
  • Wildlife

    • beneficial insects
    • bees
    • butterflies
    • hummingbirds
  • Flower Season

    • spring
  • Foliage Season

    • deciduous
  • Texture

    • glossy

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Plant Type

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Zones

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Size

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Width: 4'-6'

  • bright shade - shade
  • even moisture - regular
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  • mostly sun - mostly shade
  • even moisture - regular
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Plant Type

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Zones

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Size

Height: 2'-4'

Width: 2'-4'

  • mostly sun - mostly shade
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Plant Type

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Zones

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Size

Height: 12'-14'

Width: 6'-12'

  • mostly sun - mostly shade
  • even moisture - regular
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Width: 2'-3'

  • mostly sun - mostly shade
  • even moisture - regular
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