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Small retaining walls for rockery - mortar?

I'm building a very small rockery and have sourced some grey stone cobbled 'bricks'. The soil behind will not be of any great weight, so the wall is more decorative thwlan anything. I'd still like it to shore up the soil behind though. 

Is there a lightweight way of sealing/mortaring the wall rather than just plugging with small stones and soil? I don't want anything heavy duty like cement/mortar used on buildings. 

Thanks in advance. 


  • The bed might not be very high but what would maybe a thought is what is grown in it. the slow but sure growth of tree and shrub roots may push against the wall. I'm speaking from experience. Lack of money didn't give me much choice but when we did replace it I'm afraid we went with brick (top layer on end) and mortar.
  • raisingirlraisingirl East Devon, on the Edge of Exmoor.Posts: 6,327
    You can make a loose dry mix with soil and some cement which will 'go off' when it gets wet. Not sure I'd bother with just two rows, to be honest.
    If you had enough, you could turn the stones though 90degrees so they are narrow end to the soil you want to retain, that would make them more stable with no filler. At the very least, you should slightly step the upper row back so the bottom row sticks out a bit. 
    I would just plant up the edge with aubretia and erigeron and other small floppers so you largely hide the wall and don't worry about filling it. The soil will inevitable wash into it over time unless you build it with 'proper' mortar.
    “Light thinks it travels faster than anything but it is wrong. No matter how fast light travels, it finds the darkness has always got there first” 
  • Thanks for the tips both, very useful 
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