Flowers Perennials

Phlox – A Good Plant but It Bears Watching

I worked my allotted hour or two out in the back flower borders this afternoon.  I  spent most of that time digging out phlox.

We’ve been at this location 13 years.  I brought  phlox with me that dear friends had given us years ago.  One is pink, the other white.  I like them because they’re strong and resist mildew, which is unusual for the older varieties.  When they do get mildew (which is not often) I just cut them down because they look horrible.

Pink Phlox with summer pointsetta, lipstick vine, and sedum.

The Dark Side of Phlox

In my larger borders I let them get too much of a foothold and it has turned into a nightmare. I started trying to remove all of it about 5 years ago.  Phlox doesn’t stay put and will show up several feet from the original plant and walk all over your borders from there. I think the only way you can ever remove phlox entirely would be to sift every bit of your soil and get those tiny delicate roots out. That of course is just not practical. Bottom line – phlox bears watching.

Here’s What Can Happen

For the past several years I’ve taken out every good-sized clump and pulled out every small “starter” stem with its root in the spring.  In spite of that, it’s everywhere.  It’s entwined in the roots of various shrubs which can never be totally removed unless you take out the entire shrub. (Not an option.)  It’s entwined in the iris, in the daylilies, in malva, in the rubeckia, in the rose bush, and just about everything else. And as long as a little thin piece of that root is there — it will continue to grow.

The beauty of this white phlox is hard to beat. The white is much slower to get out of control.

Even though I hope to be gardening at 100 years of age, I really don’t want to be digging out phlox.  I wish I had never let it get started.

I talked recently to the friends who gave me the phlox and lo and behold they have removed it from their borders just for the very reason I’m talking about.

In my narrow fence border I have Phlox paniculata David and Caroline which thus far have seemed very controllable.  I want them but I’m constantly on the look out for any signs of takeover and spreading. And I keep the clumps VERY small.

Final Words on Phlox

Be forewarned.  Phlox is a beautiful garden plant and can be the backbone for color in the summer garden — but think before you plant. If you do plant — watch for signs of take over and pull it up immediately —unless you want to deal with it for the rest of your days.

Bees and butterflies love phlox.


Organic Gardening is easy, efficient, effective and it’s a lot healthier.


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  • I guess I have been very lucky with my phlox. I transplantrd some from my mothers garden to mine after she passed away and it hasn’t spred. I did have some that the deer ate every spring. I never even knew what color it was because it never got to bud and bloom. I’ll keep my eyes on the phlox that I have. Thanks for the heads up.

  • I’m sure glad that you were able to get your Mom’s phlox and that it hasn’t spred rampantly. Sometime it takes a while. Also depends on soil and color.
    This is the first I’ve heard of deer eating it. Hope it will bloom for you, Danita.

  • oh yea, the deer got it every year. I finally just dug up the bunch and gave it to my sister. The only bunch thats safe is the one in the vegetable garden. That has a 6 foot fence around it. I will keep an eye on it.

  • I’m glad you’re going to keep and eye on it. Sometimes it seems to be behaving itself for several years and then all of a sudden it’s out of control. That would be awful especially in your vegetable garden because it will compete with your vegetables.

    I understand your sentimental attachment to it. It’s hard to get rid of something that belonged to someone so important to you.
    Thanks for the follow up Danita.

  • I’ve been pulling out the phlox which has gotten out of control but it leaves behind an unbelievable root system. I now plan to rototill the area hoping to get rid of all remaining roots but not sure that’s possible. My next option would be to move!

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