Phlox Are Turning Yellow And Losing Leaves

Question From: São João da Boa Vista, São Paulo, Brazil
Q: My phlox are losing their leaves and turning yellow. They are still blooming but just on a bare stem.

A: Your phlox have a fungal disease. I'd spray them with Serenade or Natria Disease Control. Both are organic and OMRI listed. Best And Happy Yardening, Nancy