I built a raised planting bed using deck rail planters. This allows each planter to be moved to different locations within the bed, or to be removed from the bed entirely, allowing the bed to be (relatively) easily moved.
I used pressure treated 2×4’s to make a simple ladder like frame, held up by four legs resting on 4×4 PT ground contact rated timbers. After painting the pressure treated 2x4s with exterior paint, I expect it to last a good long time.
In my effort to reduce daily chores, I’ve installed a drip irrigation system on a timer. Once the plants get established I hope that the drip irrigation system will soak enough of the containers so that I can stop misting the surface.