Protecting SYP outdoors

[CEPenworks]

Ran into a little problem. My son is doing an Eagle Scout project making raised bed garden boxes for the town library. He thought he was getting pressure treated 2x8 donated but it turned out to be just southern yellow pine. I am thinking raised beds with that will rot out in just a couple years. We had 2 thoughts on how to lengthen their life. One would be to paint the boards but that is going to take a lot of time having to do a couple coats and drying. The other thought was to use something like the Copper-Green wood preservative Lowes Link. I might even be able to spray that. Thoughts?

[6270_Productions]

What are the plants in the beds going to think about your chemicals?

Yes, I know "treated" lumber is also treated with chemicals.

[Stwood_]

Cedar is best. Yes, I know..........
Not a good idea to add chemicals into your garden soil. The effect.....I'm not a scientist.
Good latex paint will save those boards for several years.

[JosephP]

Wait....is paint not a chemical???

I would concerned about a copper product being toxic to the plants  Copper is an essential micronutrient, but too much is certainly fatal to plants.  But...there are copper-based fungicides made to be applied to plants.  I'd do more digging to see how much of the copper gets to plants in the beds.

If he's lucky, the SYP is long leaf pine and not further preservation needed!

[Willyou]

Two things to consider or ask as you are doing further research: 1) How much will the chemical you apply leach out ot the wood timbers when it is dry or cured vs wet? 2) If a chemical gets into to soil from the treated timber, what direction is it most likely to travel in te soil. Will it travel much in a horizontal direction and effect the plants?

[cams2705]

Just a thought ... Have you considered taking the SYP (as long as it's in perfect condition) and going to a lumberyard that stocks the pressure treated and/or knotty western red cedar (potentially cedar fence slats).  Explain the situation and see if the manager would works out some trade-in-kind.  You may have to pay a little out of pocket if there's a price difference, but consider what would you pay for the top coat finishes and the time to apply.  You're probably looking at near break-even.

[CEPenworks]

I did some more research on pressure treatment chemicals and their use in planter beds. When you look at sites that have actually done some real science they show the newer chemicals don't leach toxic levels of chemicals and there isn't enough for the plants to concentrate to toxic levels. The older stuff with arsenic and chromium are bad but very hard to find now.

I was wondering if anyone has used the copper-green stuff in ground contact and how well did it work.