That is a good question. I would say that most of the soil would not degrade as you have no roots exchanging chemicals and no moisture. I would think the only problem might be microbial. I would think that mixing in something like Dr. Earth which has soil fungus and microbial additives would recharge this soil at a cheap cost. You may discover some yellow mushrooms growing in the old soil which is common and harmless. You might call Chris Roy at Orange County Farm Supply and ask what he thinks (714-978-6500). Bill

Hey Bill,
Thanks...I think I am going to toss the 2 bags.
My concerns were microbial based. Some plumies are sensative to microbial and fungal issues when it comes to their root systems.

Thanks

I would not toss the soil I would wet them with a mild solution of peroxide

I wouldn't toss them unless being a poor choice for container gardening is an inherent issue. As long as they're dry, they should be fine. The 2 primary concerns about your soil would both pivot on moisture issues - whether the soil was saturated or remained wet for an extended period. The result of lengthy saturation and the anaerobic (airless) composting that takes place under those conditions includes the production of organic acids that can lower pH to unacceptable levels. Soils that remained damp for an extended period, but not soggy, might have suffered structurally due to soil materials breaking down from the composting process, and the value of a soil (to the plants it supports) lies primarily in its structural integrity and how well it is able to retain that integrity for the intended life of the planting or the interval between full repots.

All plants are sensitive to certain fungi, but mostly under certain cultural conditions. For instance, as long as you don't over-water, it's very unlikely that there is anything lurking in your old soil that would hurt the plant that wouldn't also be in the next product you might buy. Virtually all plants live in perfect peace next to thousands of different bacteria and fungi that are harmless under favorable cultural conditions but could become pathogenic under unfavorable cultural conditions, with the main player in that balance between good and bad being air:water retention issues.

Al

I have made soil mix it has sat for months in a closed garbage can and then I have used it without any noticeable problems.

I would just use it in garden beds if there was too much concern.