What is the shelf life of fertilizer? I have some bags that have been stored in an outside shed and wondered whether they can be used or should be discarded.



Fertilizer is typically long-lived, especially when kept dry and at a consistently moderate temperature. The most important part of storing fertilizer is to keep it dry and cool. Sheds are not the best place to store fertilizers or pesticides due to possible extreme temperatures. Still, if the fertilizer is plain crystal type (not coated slow-release fertilizer), it is probably still good to use. Even if it is slightly solidified, it can be crushed and applied in a spreader.  You should never mix fertilizer with any other product unless the product label says it is okay to do so.

Here are some links to good info about fertilizers:











Posted on 2 Aug 2007

Maggie Wolf
Horticulture Agent, Salt Lake County

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