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More Information: Rhododendron 'Thumbs Up'


R. 'Thumbs Up' 
  Photo: Tom Ahern

Predominant Flower Color:  White

Flower/Truss Description:  Flower openly funnel-shaped, 3" across, inside ivory white with a small maroon basal blotch and spots on the dorsal lobe, outside initially pink aging to ivory white with pink midribs. Lax truss has 8 flowers.

Fragrant:  No

Bloom Time:  Midseason

Foliage Description / Plant Habit:  Leaves oblong, broadly acute apex, rounded base, flat margins, 3" long, semi-glossy, deep green. Leaves retained 3 years. Dense growth habit.

Height:  2 feet in 10 years.

Cold Hardiness Temp:  -5F  ( -21C)

Parentage  (Seed Parent x Pollen Parent): 
     Mary Belle x pseudochrysanthum

Elepidote (E) or Lepidote (L):  E

Hybridized or Selected by:  Ahern

Registration Reference:  ARS 042
Note: This cultivar is not commercially available.

Glossary of plant description terminology.
Note: Bloom time and 10 year height information are approximate and can vary dependent on weather and growing conditions.
Cold hardiness temperature is also an approximate value.


American Rhododendron Society
P.O. Box 43, Craryville, NY 12521
Ph: 631-533-0375   E-Mail: member@arsoffice.org
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