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Sunday - July 26, 2015

From: Gaines, MI
Region: Midwest
Topic: Herbs/Forbs
Title: Why Don't Phlox Bloom?
Answered by: Anne Van Nest

QUESTION:

My summer phlox only bush up but never bloom. They are in full sun.

ANSWER:

Your summer phlox (I assume they are Phlox paniculata) are usually quite reliable bloomers - especially in the Northeast. They have clusters of pink, white or lavender blooms on 3-4 feet high stems in July and August.

Some possible reasons they don't bloom include:

  • Not enough sun. They need at least 6 hours of full sun.
  • Powdery mildew weakening the plant.
  • Pruning off the flower buds. Pruning the plant in early to mid-summer could delay flowering.
  • Too much nitrogen fertilizer which could cause excessive vegetative growth.
  • Not vigorous enough. Overgrown plants should be divided periodically
 

From the Image Gallery


Fall phlox
Phlox paniculata

Fall phlox
Phlox paniculata

Fall phlox
Phlox paniculata

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