Native Plants

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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

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