Best way to stop damp reaching block wall?

[Ashandiamo]

This will no doubt be a silly question but if you don’t ask, you don’t learn. Can anyone advise on the best way to stop damp reaching the block wall shown on the attached, very very rough sketch, please 😀

The block will be faced with natural stone and an adjoining terraced area will butt against the stone. The terraced area will be planted up and moisture will be present at all times. 
The block will eventually become a wall for a car port but just trying to prevent dampness seeping through. Would a DPC membrane sheet between the block and the stone wall work or am I best putting the sheet over the stone wall and cutting it away to expose the stone that will be visible? 
I’m maybe barking up the wrong tree and there is a better and simpler way of preventing the damp reaching the block?

Many thanks. 👍

Andy

[Conor]

1. Backfill behind the wall with gravel and ensure water has somehwere to go.

2. Run doc/dpm from top of the wall, under the coping, all the way down to the bottom of the wall on the retainimg side.

[Ashandiamo]

Conor,

Many thanks. Would I getaway with running the doc/rpm between the block and stone because if I have it under the coping and try to run it down the outside of the stone, it would obviously hide the stone that I’ll want exposed???

Forgive me if I’m being stupid here and missing the obvious.

I have catered for the gravel/drain etc.

Thanks

Andy