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Back to trial Phlox for Sun

Trial Garden

Phlox paniculata ‘Speed Limit 45’

5 Photos


Phlox paniculata ‘Speed Limit 45’ is a vigorous cultivar with a stunning display of densely packed, light pink inflorescences. However, the floral display was not as long lasting as other cultivars, likely due to some pest and disease stress. Powdery mildew resistance was excellent during the first year, but became problematic during the second and third years of the trial. Spider mites were also severe during the first and third years as well. Despite these challengers, ‘Speed Limit 45’ vigorously returned each and every spring.


  • Rating
  • Common Name
    Speed Limit 45 garden phlox  
  • Bloom Period
    late July—mid-August 
  • Peak Bloom
    late July 
  • Size
    44” x 30” 
  • Fragrance
  • Powdery Mildew Resistance