I have a few theories:
1) Overwatering (due to various issues, I've had to water once a week in large amounts (too much)
2) Stress from movement (due to storms and other reasons, I move the plants around several times a week
3) Too many nutrients?
Lack of branching is usually due to not enough hours of direct sunlight.
Outdoors they need a minimum of 6-8 hours of direct sunlight on their leaves to grow properly.
Defoliation will slow branch growth too....less leaves = less energy being made = less growth.
Small branching is not because of watering, wind, excess fertilizer or being moved.....just not enough light.