I'll toss out what has helped me. Background- I've had lower back problems since age 20, herniated a disc at 35. I'm 40 now and have very little low back pain, most of the time none. This is what works for me. I do not take any pain medicine, not even OTC, I don't wear a back brace.
Daily: stretching (mostly yoga postures that focus on the back such as childs pose, prayer twist, etc) also stretches on the glutes and hamstrings because tight glutes/hammies can pull your lower back out of alignment. Pigeon pose for glutes. If stretching your hammies in traditional poses hurts your lower back, try laying on your back and raise your leg straight up and grab your ankle and pull until you feel the stretch.
Daily: Strengthening - Bird Dogs (on hands and knees, raise one arm and opposite leg hold for one minute, switch), Planks.
Once a month: Acupuncture (works for me far better than the chiropractor ever did)
Once a month: Therapeutic massage (I usually have my massage 2 weeks after acupuncture to break it up)
Don't forget that some supplements have been linked to reducing back pain- Vitamin D in particular. Take your D.
High Weight: 225
Weight at start of Primal: 189
Current Weight: 174
Goal Weight: 130
Primal Start Date: 11/26/2012