A classic tire planter
There has been a growing trend in "environmentally conscious" individuals to use old tires for a multitude of garden and household project. While I am a huge proponent of recycling, reusing, and repurposing, (see my post on Permaculture Principle Six: Produce No Waste), I have a growing concern about the health risks of using old tires.
There have been a number of studies that have shown that using old tires may not be such a good idea. There are two main issues with old tires. First, tires contain heavy metals, zinc, rubber chemicals, vulcanization chemicals (from the process of vulcanizing rubber), and other pollutants. Second, these potentially dangerous chemicals have been shown to leach from tires when placed in wet soil… like the wet soil found in a garden. While it is true that whole tires will leach less pollutants than shredded tires, but it is still likely to occur no matter what form the tire is in.
Another garden planted with tires.
I don’t know if you’ve ever seen a dumped tire in a field or in the woods. I’ve seen a number of these discarded, or illegally dumped, tires. About half the time, I smell the tire before I even see it. To me, this is just more confirmation that these tires are off-gassing or polluting the environment around them.
I wish I had a great answer for what we should do with old tires, but I don’t. What I do know is that I will not be adding old tires to my garden, my food forest, or my land.
Liu, H., Mead, J., Stacer, R. Chelsea Center For Recycling And Economic Development. (1998). Environmental Impacts Of Recycling Rubber In Light Fill Applications: Summary & Evaluation Of Existing Literature University of Massachusetts
Sullivan, J. (2006) An Assessment of Environmental Toxicity and Potential Contamination from Artificial Turf using Shredded or Crumb Rubber