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Description of Rhododendron 'Red Jack'

R. 'Red Jack' 
Photo by: Fredo Schroder Nursery

Seed Parent x Pollen Parent: 

Wilgen's Ruby x May Day 

Predominant Flower Color: 


Flower / Truss Description: 

Flower funnel-shaped, 1" to 2⅜" across, strong to vivid red, unmarked. Truss has 15 to 18 flowers. 



Bloom Time: 


Height (ft.) in 10 Yrs: 

Cold Hardiness Temperature: 

-5F  (-20C)

Foliage Description / Plant Habit: 

Leaves ovate, 4" to 4" long, light green. 

Elepidote (E) or Lepidote (L): 


Boskoop Research Station 

Registration Reference: 

RHS 88 

 Note: Bloom time and 10 year height information are approximate and can vary dependent on local climate and soil conditions.
Hardiness temperature is also an approximate guideline.

American Rhododendron Society
Executive Director: P.O. Box 525,  Niagara Falls, NY 14304
Ph: 416-424-1942   Fax: 905-262-1999   E-Mail:
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