I have 3 phlox plants and every year the bottom leaves go brown and works its way up the stem but the plants always flower and by the time their flowering is over I cut the plant down because there's nothing left but brown leaves. The plants grow back each year and repeat this browning process. Can anyone tell me why this is happening and what I can do to stop it.

HI girliemac If the weather is too hot and humid phlox can suffer from powdery mildew which can make the leafs dry up and turn brown killing the foliage so keep it in a place where the air circulates..Phlox likes neutral to acid soil that is fertile and moist but also well drained and in light to medium shade.hope this helps.your friend in gardening.mike57

I cannot say for sure. But, it sounds like the plant has too few nutrients & is sacrificing the leaves for the flowers. Producing flowers for propogation is a plant's major goal.

Alternatively, you may be over-watering.

My phlox is in full sun so that may be the problem. As far as fertilizing, I have used that new product for Miracle Gro that you shake on and it's time realeased for 3 mths. I have given all my plants lots of water every day because we have been going through a dry spell. As far as the soil requirements, perhaps I should add some manure and peat moss although the plants around it are thriving. Anything is worth a try. I may divide the plant after it flowers to give it more air circulation. Thanks guys for your advise.

HI girliemac your very welcome any time.good luck with your phlox.your friend in gardening.mike57