Non toxic / non plastic way of to line wooden planter for fruit/veg

HappySad

Hi, I’m giving away all my plastic fruit/veg growing patio tubs and have replaced them with second hand wooden crates. I want to line them so they don’t rot so fast. 

What can I use to line the wooded crates that is non toxic and not plastic? Or is their a non toxic treatment I can use on the crates? 

I was thinking of Coop shopping bags; but I think that would biodegrade too quickly. Any suggestion, ideas and websites links most welcome. 

Thanks 

greyteam1959

I would not bother lining them.
Lining them will not stop them rotting.
In fact it may encourage rot by holding moisture against the wood.

twopenny

The treatment for fences, a coloured stain, cupronal or ronseal is supposed to be safe for plants but that is the growing bit. Not sure about roots or what is in it.
Worth looking to see if it is on any forums as a question or if they have their own. Maybe a live chat facility. It's very easy to apply.
Marine paint for boats should be non toxic.
In reality anything today that won't rot is likely to have plastic in it.
What about looking at old gardening books to see what was used in the past? There's often some excellent ideas.
Or get in touch with places that have victorian fruit and veg gardens and ask the gardeners there.

Slinky

greyteam1959 said:

I would not bother lining them.
Lining them will not stop them rotting.
In fact it may encourage rot by holding moisture against the wood.

If you don't line them won't there be problems with soil being washed out the sides between the planks? Assuming you are going more than one plank height of course.

theoretica

Tung oil or linseed oil are old treatments that would help.  You would want to paint it on inside and out in lots of coats over days until it stops being absorbed and leave it to dry for a bit before filing the planters.

Also consider air flow under the planter - if you set them straight down the bottoms will never dry out and rot fast, if you raise them without enough support the weight of soil will make the bottoms fall out as soon as they start weakening - what are your priorities there?

madjackslam

Do you have any old compost bags? Turn them inside out or cut them up. I've used these to line an old toy box and then plant up with bamboo. I don't think it will make much difference, but might help it to last two years rather than one (it was already falling apart).