Question From: Farmington, Missouri, United States
Q: For the past two years, my tall phlox have grown great during the Spring season. Somewhere around early to mid summer, the upper leaves would start turning yellow then brown. They have not bloomed in two years. Last year, I thought it was because I neglected to water the back of the garden, so they didn't get enough water and withered. This year, however, we have received ample rain, to the point of flooding the back garden. So, it's not insufficient rain, but maybe just the opposite. Some of my tall phlox are in front of a 6' tall solid fence, so they don't get sun until 11 a.m. or so. However, some of them are planted in full sun and are exhibiting the same symptoms. I should also tell you that these Phloxs have been planted 6 seasons ago and have only exhibited this problem for the past two seasons. Any help you can give would be greatly appreciated.
As you read on the website, I believe they have asters yellow, a fatal disease. If you are in doubt take cutting of diseased plants to your local independent garden center for a first hand ID. Best And Happy Yardening, Nancy