No idea, but what a pretty question! Btw, do you have P. Chattahoochee too? I bought 3 more this year . . . love it so much.

I'm mystified, Spritz - I have always cut them down to the ground in autumn, once they've started dying back, and they've been fine. I've lost more than I've kept though because of letting them dry out too much, or not watering soon enough when the weather's hot and dry.

I do that to protect my Penstemons from frost Spritz, but for Phlox P, I dead head mine and in the autumn cut them down to the ground, I dont pinch back 1/3rd in spring as some do with these either!

I've never read the books you do spritz. I've always cut them right down to ground level

one of my boks says this so that you dont 'lose them' when they are winter dormant.

Hmmm...I thought it was that, but I can't see why a few inches of stem would help to protect them!

Yes, Sheila, I've got various different Phlox - the 'mossy' ones, divaricatus including 'Chatahoochee', and lots of P. paniculata. Too many, really, but the clumps are lovely in the late summer.