keeping French beans watered

[Sunshine]

I remember some years ago seeing a TV programme about how to keep your beans well watered in the summer.

It was made up of a piece of guttering with the slice taken out of the top and buried under good quality soft cardboard piece followed by soil.  There was a water pipe going into the tube so you could water from the surface, which retained more of the water.

Does any one know of this system?...   I can not recall if the cardboard sat on top of the pipe or went into the pipe to soak up the water.  If you have tried it does it work?

Was I dreaming?.