Today I installed about 90% of the plastic lining for the renovated raised bed.
My helper poured two buckets of good garden soil in the trench on one side. I smoothed it. That will get some trench composting of kitchen scraps for a few weeks, before fully covering.
If one is going to use this type of slotted cornerstone / 2x6 structure, the higher rebar with drilled 2x4s for strengthening are necessary. I learned the hard lesson, without those strengtheners it will gradually splay outward and fall apart. Then it's a LOT of work renovating it.
I do want to stain the 2x4s and maybe the sides, but that has to wait for dry season, maybe April or May.