Food safe sleeper beds

[livpoksoc]

I have just cut up some UC4 treated sleepers fo make some raised beds ready to grow veg in. But a friend said that even treated sleepers will rot if soil is left up against them, and he recommended lining them with plastic - but I was wondering if that was a safe material that won't leach bad things into the soil?

In terms of drainage, I was planning on laying a plastic membrane on the dug out ground, them pea gravel on top, then placing the sleepers on that, potentially just wrapping the inner walls and feet with something to protect them, but can't find any clear guidance on a safe material to use

 

[Poacher]

Butyl pond liner?

 

[Pat "5mph"]

Ime, eventually all wood rots, actually, it becomes compost, so all good.
No worries, it takes years, I have a planter made of pallets that still stands strong after 10 years, not rotted yet.
Every time I have used plastic in the garden I came to regret it, eventually it shreds, rips, bits of plastic allover the place.
Weeds grow through the plastic, their roots become embedded, hard to remove, shredding the plastic while one tries to remove the weeds.

 

[88robb]

Right, just line the inside walls with thick polythene to stop the soil touching the sleepers. Poke plenty of holes in it at the bottom for drainage, but don't put any plastic under the soil or your plants will drown.

 

[T4tomo]

You will almost certainly die before the sleepers rot. I wouldn't bother lining them with anything.

 

[Alex321]

We haven't used sleepers, but have used regular softwood treated for outdoor use for our beds.

We line the sides with old compost bags, cut open, stapled to the top and then just held against the base by soil.

 

[mistyoptic]

We made raised beds using this range of products. Been very pleased with them

https://www.solwayrecycling.co.uk/shop/home-garden-communities/raised-beds/standard-raised-bed

 

[Drago]

I blagged some new scaffold boards rrom the builders.

 

[N0bodyOfTheGoat]

If you have no plastic on the bed base, to prevent flooding, don't you risk chemicals in the sleepers leeching into the water and then being absorbed by the plants? Only a potential issue if you're growing edible plants.

 

[Pat "5mph"]

If you have no plastic on the bed base, to prevent flooding, don't you risk chemicals in the sleepers leeching into the water and then being absorbed by the plants? Only a potential issue if you're growing edible plants.

One must use HT treated pallets, the wood is safe for growing food.
I guess it's the same for sleepers, or any kind of wood used for growing.
If it's sold for making raised beds it will be safe.
I made some lovely raised beds by using logs and long branches left behind by the tree surgeon.

 

[livpoksoc]

So the sleepers are treated as safe for a veg garden, and intention is to grow root veg in one, and beans/courgettes in the other.

As per this thread, seems there are varying ideas. I suppose using the bags that the tomato compost comes in would be fine given they are sold as 'grow in the bag'. Will give that a go.

As for plastic in the earth itself, that'll be 6 inches below the surface of the pea gravel and intentional to stop some pretty narly weeds growing up as these are to be sited where bad weeds have blighted my garden for years.

 

[Pat "5mph"]

As for plastic in the earth itself, that'll be 6 inches below the surface of the pea gravel and intentional to stop some pretty narly weeds growing up as these are to be sited where bad weeds have blighted my garden for years.

You are planning to dig out the ground then place the sleepers on the digged out square/rectangle, correct?
In doing so you will remove most weeds, you will also bring some weed seeds to the surface.
Ime, do not bother with the plastic and the gravel, because the weeds eventually will come back, some will grow through your barriers, others will find the light sideways, next to your beds.
I would, after excavation, lay down 4 layers of cardboard, making sure to block the light out for the weeds.
The cardboard needs to be plain, no shiny bits (plastic), amazon boxes are ideal, raid the neighbor's recycling bin, the local shop's, your work, anybody
No need to wet the cardboard because we are still in the wet season.
After the cardboard, lay down some garden waste, chopped up if you can, leaves, kitchen waste, anything compostable.
Top this up with compost.
As I said, weeds old and new will come back in maybe a couple of seasons, but this way is cheaper, environmentally friendly and you won't find umpteen wee stones in your growing area.
Tldr: Google No Dig Gardening

 

[PaulSB]

@livpoksoc listen to @Pat"5mph" she's absolutely spot on. The plastic and gravel is a waste of time, effort and money and has the potential to be detrimental to your beds.

I made new beds 12 years ago with treated timbers placed directly onto soil. The beds are 9" deep and filled with soil to the top of the sleepers. No sign of rot yet. Lining these with plastic will simply get in your way.

 

[nogoodnamesleft]

I made some raised beds from treated 4" x 2" timber and 5 years later rotted and falling apart. If I ever feel inclined to use raised beds again I probably look at some sort of stone or brick. Undoubtably more expensive and involved but at least they should last better.

 

[livpoksoc]

Thanks all for your replies and guidance. I suppose I couldn't help myself wanting to be thorough as the spot I'm putting these are where our most gnarly weeds are.

So I did dig out, lay a membrane, then gravel on top. I have then put wire mesh underneath as there are rats roaming the streets and parkland here (thanks council for building on greenfield!)

Frames have now been built and just need to add the soil and plant some seeds!

Having got the bug, I am going to get some wooden borders to expand this further down, but plant out with flowers where this catches the sun.