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Rescuing soil after years of membrane and stones?


My little garden has been underneath a membrane/stones and a membrane/decking for years. I've managed to get rid of all of it, but the uncovered soil is clay-based, compacted, and stoney.

I assume I need to dig it with a fork at the very least to allow some aeration, as well as adding some compost, sand, mulch?

I'm planning to make some raised beds but would like to improve the existing soil first. Do I need to delay building the raised beds ideally, even to next spring, or can I just turn the existing soil with some compost, sand, mulch and then put the raised bed on top now?




  • Hostafan1Hostafan1 Posts: 34,053

    If you're making raised beds, it doesn't matter what's there now , as you're raising the soil level

  • If a bed is raised by more than 30cm, is there any 'blending' between the existing soil and the new bed soil? Do worms eventually mix the two soils or is the bed effectively just plonked on top of the ground?

    I suppose I'm wondering whether a raised bed is avoiding the problem of the poorly soil rather than dealing with it, or whether I can do both image

  • PosyPosy Posts: 3,601

    Well, ask yourself what you will gain from a raised bed before you start work on it. With clay soil, you might want improved drainage or a mix that will support plants that need light soil. In this case you should break up the clay base to avoid creating a 'pan' - an almost impenetrable layer beneath the bed. Some roots, such as shrubs and larger perennials will go through to the clay soil but without digging, it will take donkey's years for the worms to mix it all up. If you just want a garden with reasonable soil, rather than raised beds dig in as much organic material as you can get, add grit as well and mulch as often as you have the strength! You can, of course, have raised beds and beds which are not raised.

  • Thanks!

    The current soil is quite stoney - possibly from a previous attempt to put stones on the garden before they opted for a membrane. Should I try to remove as many stones as possible when digging it?

    Also, is there a gardener's 'bible' that all beginners should have? Someone mentioned Mel Bartholomew, but are there any others? image


  • Does everyone agree with Verdun re raised beds? I was going to have raised beds for my fruit (eg raspberries, gooseberries, blackcurrants, strawberries) - about 8inch high- as I'm on clay. Maybe I should rethink?
  • FairygirlFairygirl Posts: 52,134

    I have both - some raised beds which are on an area which was all paving and gravel when I moved here, and a longer border which was compacted grass. Clay soil - very heavy in most places.

    We get high rainfall so the raised beds allow me to create the medium I want for lots of  plants - it also brings some plants up nearer eye level and as the beds are different heights, it gives a bit of variety. The ordinary border had loads of locally provided horse manure on it for a winter before I put plants in. Everything is growing very well. image

    I think I'd do a bit of both 30x7, but it largely depends what you want to grow and what other things you want in the garden, like a dining/seating area, clothes drying etc. No point in going mad with manure and digging grit in the areas you might want paving or paths.  What kind of look are you aiming for? 

    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • PosyPosy Posts: 3,601

    We have clay soil which gets quite waterlogged in winter. Effective drainage would be a major engineering project so I find that I have to choose my plants carefully and building up or raising some areas has been very successful. Raspberries wouldn't grow for me on clay and I think carrots object, too but I have given up fruit and veg so I can't be much help.

  • image


     Things might not be as bad as I thought. I turned it once with a fork, haven't added anything yet, and it's quite loose soil under the compacted surface, almost a bit crumbly. And I saw worms, so maybe the breached membrane allowed some useful creatures to get under there. Or maybe the owner before the one who laid the membrane was a gardener image

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