Who put the peace beds in the Park?

The “peace beds” in Central park are failing to thrive and there is a proposal to give up and grass them over.  I am trying to establish exactly what the problem is, before deciding what I think of this.

Meanwhile I have no idea who put them there, or funded them.  Or when they were put there.

Or why.  Was it an event which inspired this?

I just suddenly noticed them one day and wondered how many hundreds of times I’d walked straight past them without spotting the CND symbol all cut out and planted up.
Does anybody know?