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Raised bed filling

I have built a raised bed made from concrete paving slabs. During the excavation for the foundfation I dug up some roots from a mountain ash tree, they are long trailing roots of aprox 1.5 centimeteres tapering to nothing, they havebeen out of the ground for over two weeks now. would it be ok to drop theses into the bottom of the taised bed along wwith other garden rubbish.


  • FairygirlFairygirl Posts: 54,837
    What depth is the bed and what are you using it for?
    A raised bed drains more quickly, so you do need a decent soil based medium in it. Anything less, ie compost, isn't hearty enough for long term planting. 
    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • The bed is 1.8 mts (6ft) x 1.2mts (4ft) x 0.6mts (2ft),most likely vegetables, ie lettuce, carrots , beetroot etc.

    Its the good ladies project, she has back problems so we thought we would give this a go.

    We have seen on the internet that garden rubish, old rotted wood, tree branches and old turfs are laid on top of drainage material.

    I am going to lay some old stone pieces in the base then cover with a 50cm layer of pebbles then lay some weed membrane over the lot then start filling with the garden rubbish etc then the soil and compost.

    Its knowing how much soil to compost we will need to fill the bed.

    Thank you for your comments 

    Kind regards

    Mel West
  • As long as the root is dead, it's fine. You need a surprisingly large amount of soil-type material to fill a box that big, so any veg/kitchen rubbish, wood shavings, newspaper etc. that will eventually rot down is good. You don't have to fill completely to the top the first year, and even if you do, you will need to add more the second year as the soil settles.

    I found about two 50kg bags of soil based material raised the level of my bed by about two inches, but the area of mine is about six foot by three foot.
  • Thank you for your comments, very much appreciated, I don't suppose there is any way in telling if the roots are stiil active.


  • They will rot down.

  • nick615nick615 Posts: 1,481
    I imagine, if you want to make doubly sure, crush the roots with the heaviest hammer you can find?
  • Hello, please could you tell me where you found the information on what to put inside the raised bed? I am about to make my own ready for next spring but I didnt realise you need to put drainage and weed proof layer etc. (I'm very new to this)
    This is what I was going to follow, but all it really says is to put soil and some organic matter (I am assuming that means things that usually go in the compost bin). 
    I do have lots of branches that I was going to take to the déchèterie, so maybe I can put them in! 
  • I think quite a bit of this comes from experience, unfortunately. For example, I live where the soil is naturally heavy clay, it just doesn't drain. If I were to build another raised bed, I'd put more and bigger stones at the base. I'd also build a bit higher and incorporate seats at the corners.

    I might think about a weed proof layer, because bindweed roots are hideous to dig all the way out, but that's really only once a year so maybe not.

    I put about two big bags of used rabbit bedding (mostly sawdust) near the bottom and spent a year wondering if it had rotted down, it did, into lovely crumbly stuff. What else went in? any kitchen veg bits, prunings of smaller branches, dead summer bedding plants, leaves. I had a grand clear out of all specialist composts (orchid, rose, ericaceous) and out of date fertiliser. And then the soil. All big bits of rock removed, and I tried to mix with the compost.

    If you have wonderful, crumbly, fertile soil, then you can just dig it up and put it in the box. For the rest of us, a raised bed is a chance to change our native soil for a  'new, improved' version.
  • FairygirlFairygirl Posts: 54,837
    @English_girl_in_France - you need a mix of soil and compost or other organic matter for a raised bed. Not compost alone. All raised beds drop after a while, so you'll need to top them up.
    The depth of the bed and what you grow are factors. If you just chuck a lot of branches etc in, they'll create gaps so your soil medium will drop through it. Not a great idea.
    However, if the bed's over 18 inches deep or so, you can partially fill it with other material, but you really need to add a layer of something to prevent everything dropping through - cardboard, newspaper, landscape fabric etc.
    I have turf in the bottom of most of mine, depending on the depth. My beds all vary in height from less than a foot,  to about 2 feet. They're all varying widths too, built to fit the perimeter fences etc. They all have 'coping' edges round them as they're ornamental not functional, the way veg beds might be. Branches would need shredded, not left in big pieces.  :)

    As @seacrows says - it's not a standardised method - it depends on various factors.
    It's also easy for people to say the roots will rot down, but it isn't that simple @melvyn.westYTyIdjmj. Seacrows advice is very good regarding that.  :)
    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • NewBoy2NewBoy2 Posts: 1,813
    Basic info.

    My RB is 3 scaffold boards deep...........27 inches.

    I filled it a layer of big pebbles then alternate layers of fresh bagged top soil and horse manure.

    First year I took 15 minutes trying to get a 3 foot long parsnip out

    After 5 years I have had to replace the boards.

    Good luck
    Everyone is just trying to be Happy.....So lets help Them.
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