Wood preservative for sleepers with a raised bed

I'm building raised beds this spring for veg. I've bought untreated oak sleepers for it, and dug trenches for a bit of concrete to lay them on. Next step is treating the sleepers with something non-toxic to stop them rotting and also not poison is when we eat the veg.

Hitting Google, I found this which looks a bit different to your basic Ronseal.

https://www.thenaturalgardener.co.u...t.php?osCsid=048c90cd3f975fd33775fba315df8a52.

Has anyone used this before, or can advise?

Oh, and by the way, how deep do people usually make the footings? I've got 200x100mm sleepers, and I'll be stacking them 3 high on the narrow side to get more height (600mm total). I'm planning on about 20cm deep of dry laid concrete, and drive rebar rods through the bottom sleeper into the concrete (and soil below) to hold it together. Is that enough? Or do I need more concrete to keep the walls upright?

 

That seller appears to be attributing preservative properties to a product which the manufacturer only markets as a stain

Manufacturer's website LifeTime® Wood Treatment Non-Toxic Wood Stain

Another supplier's website LifeTime Wood Treatment


P.S. If re-googling produces a product called 'Timbersil' read this first (and google 'timbersil failure') TimberSIL Wood Product Tied To Allegations - Parker Waichman LLP

 

I am not sure what wood treatment is safe for growing veg. For outside wood I have used Danish Oil on outside wood ( pine ). Gives a lovely finish, is safe for food , but after a year looks awful. Screwfix outside wood oil was the same. For outside wood treatment, to show the grain, I have found Ronseal 10 year to be excellent. It is water based and very easy to apply. My gate looks perfect after over 3 years weathering.
The site below may give you some info on treatments.
If they are nice oak sleepers, maybe no treatment would be best. Just jet wash them when they get grubby. I am sure the community garden raised beds near me have no treatment.

Buy Wood Finishes, Waxes, Stains, Varnishes and more

 

@HarryS I use this found it to be really good. I've used it on decking frames and raised beds too, I also nail dpm on the inside of the raised beds.

Barrettine Wood Preserver | Barrettine Products

 

I made up a couple of small raised beds using some untreated scrap timber last year. I've been growing veg in them and, like you, I wanted to find a non toxic treatment for the wood.

I found this; Eco Wood Treatment - also from Canada. I made and treated the beds in May last year and so far there's no sign of any rot or deterioration, although the beds are not yet a year old so I can't say how it will perform in the longer term.

As for toxicity - we grew lettuce, radish, spring onions, tomatoes, courgettes and parsley in the beds last year, all of which we ate with no ill effects!

You can see a couple of photos of the newly treated beds before I planted them up, in my post from another thread here. I have to say so far I'm quite happy with the results.

 

Graham B. Thanks for sharing your post. Yes, the preservative you mention sounds good, also those that other members have quoted. However you say that you are using oak untreated railway sleepers. Just a thought. Taking into account the dimensions of the timber/sleepers, am sure that used untreated they will probably see you out-lifespan wise. Just a thought. Good Luck with your project.

 

Thanks folks.

Trunky, that does sound like the same stuff under a different name. I wouldn't expect even untreated softwood to show much deterioration after only a year, so like you say it's not serious confirmation. It sounds like kind of a chalk wash, and I'm not sure how that would help.

Mike, that's why I bought oak - but then researching online, I've found people who've had oak sleepers rot out in 5 years, and I'm not going for that.