Forward Fold
Forward folding is great for stretching the muscles on the back of the legs (glutes, hamstrings, calves, etc.), which, if they are tight, can create a downward pull on the hips and therefore on the low back. The key to forward folding is bending forward from the hips. This may require you to bend your knees and/or not go down as low. I am using blocks in the photo but you can use a chair or even a table if bending forward with your hips is not something you are used to doing.
Wide-Legged Forward Fold
Like a regular forward fold, this pose can stretch muscles on the back of the legs that, if tight, can create a downward force that travels up to the the low back. However, there are two important differences. The first is that this pose makes it easier for those of us with some extra padding to lower down more deeply so that we can achieve a greater stretch. The second is that this pose also stretches some of the muscles of the inner thigh that connect to the hips. Like in a regular forward fold, it may be helpful to bend the knees and/or not go as far down so that you can achieve a greater tilt forward at the hips.
Reclined Lizard
This pose is targeted towards the adductor magnus muscle - a muscle on the inner thigh that helps the hamstring muscles. Because it is the longest muscle on the inner thighs, it doesn't always get a full stretch in the wide forward fold, so this is a great way to get some length there. A side effect of this pose is that it gives a gentle stretch to some of the muscles on the front of the opposite hip, warming them up for the next pose.
Supported High Lunge
The back leg in a high lunge stretches many of the muscles that attach to the front of the hip. Tightness in these muscles can also create a pull down the front of your body that results in low back pain. The more upright your torso and the deeper the bend in the front knee in this pose, the deeper the stretch. In this variation, I've used the back of a chair for additional support. The chair also helps to take some of the work and out of the pose and makes it much easier to balance.
Supine Pigeon
This stretch is great for the piriformis muscles, located on the outer hips. When tight, this muscle can compress the sciatic nerve sometimes causing pain to radiate up to the lower back (and back down the leg). If you experience this kind of chronic low back pain, stretching the piriformis may alleviate your discomfort.
Seated Spinal Twist
Most twisting poses stretch the muscles on the outer and back of the hips (with the usual exception for the piriformis muscle). When any of these muscles are tight, they can pull the hips out of alignment causing strain to the lower back. Pictured is a single-leg seated twist. If placing the elbow over the knee is too difficult, you can just hug your leg as you twist.