Can pressure treated wood be used in vegetable gardens?

Hi! We have some pressure treated wood that we would like to make raised beds for veggies. Since copper is now used instead of arsenic to treat the wood can it be used? And if so should we line it? Margaret

I haven't seen the copper treated stuff, but have heard of some treated with citrus extacts, which seems safe enough. I wonder more about the copper being safe for plants than being safe for humans...

My understanding (even with the old arsenic treated stuff) is that as long as the wood is properly sealed, nothing from the wood will leach into your garden soil. So if you slap a couple coats of polyurethane on those boards (no need to be artistic about it), you'll be fine.

For over 30 years I have used treated 4x6's and others around and in my beds..If it's been harmful to us or plants I don't know it yet. lol..

Larkie

Pressure treated is what we've had for years at various homes with no problems.

Same here. I love the stuff. I grow all my veggies and most herbs in treated lumber raised beds. Haven't noticed any ill effects in 20 years.

the press on it is terrible. Copper and cyanide and arsenic........does sound like a good idea if you can avoid it but in FL you might not have too many choices. How about cypress?

Cypress is great if you can afford it. It used to used in greenhouses a lot. But now it's really expensive even if you can find it.

Thanks everyone for your input. This raised bed concept is new to us, but we're jumping in with both feet this Spring. We've expanded our garden size to accomodate four 4x8 beds since we're still harvesting our winter crops in our existing beds. The choices for wood are definitely limited in the Florida climate if you want them to last more than one season. My husband was building the beds when we started wondering if it was much ado about nothing with the pressure treated so I told him "Wait! I'll just plug my question in the DG and lots of wonderful people will give me the info I need." Margaret

Pressure-treated? No thanks - not for me! I'd use concrete blocks or recycled plastic panels. I've seen the patio roofing panels cut in three-foot widths and set in place with with rebar sticks. It can be sunk about six inches down to prevent grass from creeping under.

Veggie,
I heard a scientist say that the amt of chems that leaches out into an actual plant is so miniscule that it wouldn't hurt you. If it won't kill the plants, then it won't kill us LOL!! Now if the plants start dying.......

Prob no worse than anything else in our gardens, IMO.

If Larkie gets sick we'd better worry!!

lol...

Different studies have shown different results with regard to leaching into the soil, but all studies seem to agree that pressure treated wood that has been sealed with a coat or two of polyurethane leaches nothing at all into the soil.

I gave our deck posts a quick coat of polyurethane stain before they went into the ground, figuring it was best to be safe. It's an easy step to take, and then you'll have no concerns about your raised garden.

I've used 1x1 by 8 foot pressure treated stakes for my tomato plants for years and they'll last almost forever. I've also read that there's probably more arsenic in your drinking water than what will leach out into your garden from pt lumber.

I'm sure that's true. I'm just saying that for anybody who might still have concerns, sealing the wood would take care of it. Frankly, half the reason I sealed our deck posts was so my MIL would quit worrying about it.

Either way, I don't think you need to be concerned about using pressure treated wood to build raised beds.

I guess I appear to be one of the few that would be concerned.

Yes, many tests have been performed, some showing that the leaching is minimal, some showing that it is detrimental. It seems to be a long term process (this leaching) will only have an impact on humans once the soil is saturated. It's also been show that plants definitely take up the poisons and, of course, we then eat the plants, and the toxins are passed on up the food chain (that's us). However, for it to show any affects it may take years to show up in adults. As for children, they are much more susceptible to absorbing the poisons. (Research, even when conducted by Monsanto/DuPont has shown that children seem to readily absorb residue either from playing on pt decks or, worse yet, underneath them.)

From a report: "A draft EPA study issued last month found that the lifetime risk of an arsenic-related cancer for children who play frequently on CCA-treated structures could be as high as one in 100,000 — 10 times the one-in-a-million threshold the agency usually considers to be a significant public health threat." (NOTE: that quote taken from a 2003 report.)

veggiemom, copper has always been used in treated lumber. "CCA" stands for "chromated copper arsenate" (copper and arsenic). Fortunately the EPA halted sales of CCA treated lumber to home-owners last year (or year before?) after years of a big battle over it, however it is still available to professional construction companies but reserved for certain building purposes. (By the way, Big Red, yes, arsenic in the soil is very minimal, but the amount you find in pt lumber is huge and can't be compared. It's like comparing the amount of N in the air we breath (minimal) to breathing in a full breath of N from a compressed tank, so to speak.)

Pesonally, I think arsenic is one of the many elements of life and like all elements there is a place for it; too much, or too little, can be detrimental though, just like an overdose of water would be.

The new treatment for lumber is also "in the air". It is supposed to be "ACQ" "alkaline copper quat". Some lumber companies want to use ACC (the latter "C" being chromium, also a cancer causing chemical, just like the former "chromated copper arsenate").

What is importortant, at this stage, is YES...seal your lumber and do it more than once if you like. One sealant will not last a lifetime. Remember, just because you are not immediately affected doesn't mean your offspring, or the following inhabitants of this Earth, will not be affected by it.

(Hehehe...I'm sorry...I can't believe I found a soapbox to stand on! But before I stop yapping, lemme tell ya why I went on for so long...)

In 1988 the general consensus was that "railroad crossties, if 20 yrs old or older, will not leach their chemicals into the ground and are safe for homeowner/consumer use". And get this...I read that from Organic Gardening/Rodale Institute when I was heavily into teaching organic gardening techniques. The thing is, 15 years later it was discovered that that statement was "incorrect". (Many of ya'll know that railroad cross ties are treated with creosote, a well-known carcinogen.) Oh well...by then, what with the crossties in a small area of my garden all those years I couldn't comfortably tell myself, or others, that my crops were organically safe. (We now use that area strictly for flowers.) Go figger, eh?

Since then I've really delved into many aspects of pollution, contaminants, potential pollution/contaminants, and am very wary of many aspects of big business/agri-business, etc. However, I also wonder what we'll find in another 20 years from now. Hopefully all this fretting is for nought, eh? Cross your fingers, friends. (I still prefer to hope for the best and look for the positive!)

I think you really have to look into everthing these days
on who says what or whatever.
pressure treated wood is bad for everyone they say now,
so now you see PVC playgrounds poping up all over town.
but have you ever seen the studies on PVC .. I've seen a few
and i think i would reather have the pressure treated wood back.
who do you believe ? ...

Just my vote, I wouldn't use it around food!

Some of us are more chemically sensitive than others and I would avoid the treated stuff. A cheap alternative that supposedly lasts for years is untreated pine with a couple coats of boiled linseed oil. You'd need to get the wood at a local sawmill.

Agrinerd, (Howdy Keith!)...I just finished a raised bed to day. Was gonna do the linseed oil (or mineral oil) but the rough cut lumber from the mill was so cheap I just decided to try it as is. (Friend of mine had untreated/un-oiled rough cut in his beds and they easily lasted 4 yrs. I figger that is a good trade-off...will just replace them when they rot.) (Some folks tell me their wood last longer but I believe it will depend on the wood....they say pine will last longer than oak. I always thought the opposite was true.) Live and learn, eh?

I agree, on all counts.