My phlox flowers are not as spectacular this year, why?
Make sure your phlox getting enough sunlight, and the soil is moist. Phlox needs 4 to 6 hours of direct sunlight at minimum, and it do not do well in hot dry soils.
Do you fertilize your phlox? Applying Miracle-Gro one time per month should be ample. If your phlox does not bloom next year, you may want to rip it out and begin anew.