I too suffer occasionally from lower back pain. To maintain a healthy back, I have to stretch, strengthen and manipulate either by SMR or deep tissue massage. Floor stretches are very effective to help loosen tight fascia and muscles but it can become mundane after some time. Why not try these TRX stretches that specifically target muscles related to lower back problem.
Lower Back Stretch
Lower Back Stretch with Rotation
Piriformis/Glute Stretch
Spinal Extension Stretch
Side Stretch
Hamstring Stretch
To find out more information on my rehabilitation program, check out my Online Personal Training Rehabilitation Program for common lower back, knee and shoulder injuries.