| Someone on another forum (not GardenWeb) recently found a couple of bags of "old" potting mix. She's not sure how old, but it is at her mom's and her mom hasn't planted anything in some time.
She's wondering if it's OK to use.
So far the only concern that anyone has identified is one of decay - how quickly can a potting mix decay in a bag thereby lowering the pH and breaking down the material to a much smaller form? As far as I know it's in a dry place, not wet, so that would make the decay happen at a slower rate.
I'd love to hear thoughts from folks here. I looked for some studies (briefly, I admit), but couldn't find any.
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