Some hippies make a big deal out of not using treated wood, which just seems it'll rot that much faster.

I've heard the chemical argument is nonsense, or at least overblown.

Your thoughts, from non-hippies?

I wouldn't worry about it unless you were using treated wood as a mulch or something.

"Treated wood" is soaked in arsenic and who knows what else. I would never use them for planting anything you might eat, or anything your pets might eat or you children might chew on as the arsenic will leach out into the soil and the plants will take up the arsenic.

It is best to stay away from such things when growing food.

Otherwise, they may be used for decks and ornamental gardens.

I've had really good experiences using cinder blocks to build raised beds for a vegetable garden.   :farmer:

My garden is flat with the groud - I've been thinking of using wood to raise it but I'm going to follow Matthew's example of bricks.  In the future - I'm still too sore from manually expanding the garden...   :smile:

"Treated wood" is soaked in arsenic and who knows what else. I would never use them for planting anything you might eat, or anything your pets might eat or you children might chew on as the arsenic will leach out into the soil and the plants will take up the arsenic.

If you buy produce from the grocery store, I can promise you that you've consumed, on a regular basis, chemicals, that were sprayed directly on the plant/fruit, and are many times more toxic than arsenic.

That being so, I'm not going to worry about a little arsenic that may or may not leach from the edge of the garden bed or container, and that may or may not be taken up by the plant.

Actually, the cinder blocks are quite easy to move around. To solve the weeds growing up in the holes, I put a thick layer of mulch under the beds to smother the weeds (this was in Colorado and they have some really nasty weeds that spring up when one tills the ground). I also planted herbs in the holes to use all the space I could.

As far as "a little arsenic" -- I thought one of the main points of growing your own vegetables was to have clean produce.

There's a good, balanced article on the Fine Gardening web site:  Does Pressure-Treated Wood Belong in Gardens on this topic. The article points out some precautions to take whenever a person uses pressure-treated lumber:

(Pressure-treated lumber is also called CCA lumber. CCA=chromated copper arsenate)

If you use CCA lumber...
The chemicals in pressure-treated lumber are pesticides, so you should handle the wood with the same precautions as befit any potentially hazardous material.

Protect yourself while working with CCA wood. Always wear gloves, eye protection, and most important, a dust mask. Long sleeves are a good idea, too. Wash yourself and your clothes afterward. Finally, clean up every speck of sawdust you can (a shop vac does the best job). Drilling and sawing over a paved surface makes dust retrieval easier. Bag up sawdust and wood scraps and send them to the landfill. Don’t consider these steps optional.

Never, ever, burn CCA-treated wood. Burning sends some of the arsenic up in smoke, which can be inhaled. The ash, too, contains high concentrations of arsenic.

There are things you can do to CCA-treated wood to minimize leaching or migration. Scrubbing the wood with detergent or power washing it will remove surface residue. If possible, let the boards weather for several months after they’ve been cut and drilled before assembling. Studies show the greatest amount of leaching occurs the first rainy season. Always predrill holes for screws, which will prevent cracks in the wood. Cracks are places where preservative can leach. Lining the inside of the bed with heavy-duty plastic before filling it will create a physical barrier to any CCA compounds moving into your soil. Painting exposed wood surfaces with water-repellent finish, paint, or stain will protect your skin if you lean or kneel on the sides. And if you have small children, it will also prevent CCA compounds moving from little hands to little mouths.

Finally, you can take advantage of arsenic’s tendency to not travel far in the soil. To keep the arsenic in place, refrain from mixing soil along the perimeter few inches of the bed with soil farther in. Avoid growing spinach and root crops, particularly carrots and radishes, close to CCA-treated wood. Consider planting a band of compact flowers along the edge of the bed.

In any case, I'd recommend the cinder-blocks over wood.

They're not that heavy, and should you change your mind about how well the bed is laid out, you can make the changes more easily and more quickly than you could with wooden timbers or boards.

You don't have to drag out and use all those tools to move a few cinder-blocks.


If you do decide to go with wood, I don't think you'll have trouble finding untreated lumber. But if you do, I wouldn't let that stop you from planting your garden.