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Other than the risk of injury and tetanus, will the hundreds of rusty nails inexplicably found in sections of my garden harm the plants that grow there or the people who eat said plants? They are so rusty that they are barely even nail shaped, most are more like long, irregular rust blobs.

(Any theories on why sections of the garden have dozens of nails per square foot in the topsoil are welcome in the comments :D)

marked as duplicate by kevinsky, J. Musser, Patrick B., Niall C. Jan 21 '15 at 5:40

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  • roofers who don't clean up after themselves? – kevinsky Jan 11 '15 at 16:22
  • I have known people to put rusty nails in a garden on purpose to stimulate a bluer colour in hydrangeas but not in the quantities described. I think the effects on plants will depend on the species but if enough iron is present in the plants when you eat them, it can potentially cause some damage (look up iron poisoning). Do any of the nails still have magnetic properties? That might give you an easy way to remove them – Alpar Jan 12 '15 at 7:51

Apart from possible injuries arising from remaining pointy parts, there should not be any problem with the nails.

As @JMusser answered to my own question, rust is just iron oxide that is not harmful in any way (and even a very common part of the soil itself)! See Is rust from a steel rainwater barrel harmful to edible plants? for details.

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