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Breeze blocks planter

I have just built a thermallite breeze block large garden planter and I would like some advice on what I need to do to fill it. It will be rendered on the outside and line inside with waterproof liner. But I'm unsure if I need to put gravel/ stone in the bottom before applying the soil or is there anything else I could use.


  • K67K67 Leicestershire Posts: 2,507
    edited April 2021
    What size have you built as if it's deep it's probably cheaper to fill with some gravel or hard-core first.
    If it's open at the bottom what's the soil like.
    Usual mix for planters is multi purpose compost, John innes 3, some of your own soil and some manure. 
    I don't bother about the ratios but I remember someone gave them on another raised bed question.  
    I'll try and find it.
    Couldn't find what I was thinking of but this was from a post by @BenCotto

  • This is it before it was finished 
    It is open at the bottom. Just want to know what's best to line it before I put soil ect on top
  • K67K67 Leicestershire Posts: 2,507
    A lot of different suggestions on here over the years, from chemicals in cement leaching into the soil and moisture getting through the blocks and blowing the render. Also if you don't do sonething the blocks will take the moisture out of your soil quite fast and you will need to water a lot in a hot summer.
    I suppose it would be best to line with heavy duty plastic or damp proof membrane but is fixing it going to be a problem? 
    There are various types of waterproofing paints that you could use instead, maybe the sort you use to seal ponds with but if your inside surface is a bit uneven would it work well?
    Can't help with the sides but you need drainage so dont use plastic in the base.

  • Blue OnionBlue Onion Posts: 2,933
    Hot glue gun will fit it to the blocks long enough to backfill with soil and compost.  I wouldn't put anything on the bottom, no gravel or anything, since it's direct on the soil.  
    Utah, USA.
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