Mt Cuba Center
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Carex barrattii
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Mt. Cuba Center evaluates native plants and related cultivars for horticultural and ecological value.

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Mt Cuba Center
Back to trial Phlox for Shade

Trial Garden

Phlox divaricata ‘Mary Helen’

4 Photos


Phlox divaricata ‘Mary Helen’ initially did well during the first year of the evaluation but completely defoliated during the summer months. The stress caused by the defoliation in the first year actually reduced the size of the plants during the second year. The third year was slightly better, but summer defoliation caused by powdery mildew was a consistent concern year after year.


  • Rating
  • Common Name
    Mary Helen woodland phlox  
  • Bloom Period
  • Size
    12” x 20”