In earlier posts I shared how I made a raised bed vegetable garden. Fortunately, I used cedar wood for the garden. On the outside of the garden fence I placed smaller pressure treated wood boxes to grow flowers. 9 Boxes to be exact. The flowers serve a two-fold purpose; they make the garden look nice and they deter burrowing animals from digging under the fence and accessing my garden.

Pressure Treated Box

After a few weeks of watering the flowers in these boxes, I noted that only one of the decorative flower boxes were flourishing. The remainder were either stagnant or dying. The one box of thriving flowers was made out of leftover cedar wood from the vegetable garden. The other boxes were made from newly purchased 2” thick pressure treated wood.

Noticing this growing anomaly I decided to do a little research on pressure treated wood. I was a little surprised when I read warnings such as use gloves when handling pressure treated wood, chemicals can leach when the wood comes into contact with water, and to wash work clothes separately from other household clothing before wearing them again. Prior to 2003 arsenic was used as one of the chemicals in treating the wood. Post 2003 copper and/or chromium replaced arsenic. The newer pressure treated wood is purportedly safer.

More Pressure Treated Wood Research

I then read further where gardeners were asking whether or not pressure treated wood is safe for vegetable gardens. The answers were mixed. It usually depended upon which chemicals were used for treating the wood.

Not being a scientist or chemist or even a seasoned gardener for that matter, I didn’t like the sounds of the chemical treatments. Unfortunately, I didn’t do my research prior to creating the smaller decorative garden boxes.

To make matters worse, I was knee deep in a front yard project that involved making more garden boxes out of pressure treated wood. Since I wouldn’t be eating the flowers planted in those flowers I didn’t think pressure treated wood would be harmful. I’ve since had a change of heart and mind.

Repurposing Pressure Treated Wood

I’ve dismantled the garden boxes at the front of the house and have repurposed them. I made shelving to hold my gardening tools/supplies. I also made a rolling base for our large, heavy generator. I’ve replaced the pressure treated wood with cedar.

The smaller garden boxes that line the outside of my garden will stay in place this year. There are 8 of them and the dimensions are 6’ by 6”. Because the newer wood is deemed “safe” and I won’t be eating the contents of the boxes, I’ll leave them. Plus, the job is just a little more than I’m willing to tackle at this time.

I’ll handle the potential chemical leaching with EM1  (effective microorganisms). After all, if EM1 can reduce the radiation levels in one Fukishima gardener’s fruit to a level of ND (not detectable), I’m sure it can remediate leached chemicals from pressure treated wood.

Additional Reading:
http://www.finegardening.com/does-pressure-treated-wood-belong-your-garden

http://www.naturalhandyman.com/iip/infxtra/infpre.html

http://extension.psu.edu/plants/crops/esi/treated-lumber

http://www.dec.ny.gov/chemical/8790.html