Pressure treated wood for grow boxes?

Hi all,

I’ve got a bunch of pressure treated lumber leftover from a non-bonsai project and I was wondering if anyone knows if it’s okay to use for grow boxes or will the chemicals be harmful to the tree?

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I stay away from pressure treated lumber for my grow boxes. Depending on the pressure treatment method, the chemicals can be phytotoxic.


I use them because I had them. Open mesh bottoms. I do/did worry about whether or not it would be toxic, but :man_shrugging:t4: I guess I’ll find out in a few years. I’m making my next box out of cedar to see how it holds up. You can also find like old recycled wood on FB for cheap. I found some on the side of the road.

reclaimed pallets would also be an option. +1 for the cautious approach to treated wood. It normally takes quite some time for a box to break up if the panels were not made from too thin panels to start with.

I’ve used Pressure Treated lumber for a number of years. The old opinion of not using it came from when arsenic was used as the preservative.
The newer PT is preserved with a copper based preservative.
My only suggestion is to let it weather for a year outside prior to use.

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Thanks for the advice!