The Grass Doctor

Does granulated fertilizer go bad or expire?

I don't have a very big yard and have some leftover fertilizer from last year, do I need to buy more or can I finish using what I already have? It was stored in an outdoor shed. It was definitly exposed to the Texas heat and humidity, but was never rained upon.

Public Comments

1. As long as the fertilizer hasn't become moist and clumped up, it is ok. The only danger is that "chunks" of fertilizer could burn your lawn, so be sure to pick out any that have formed.
2. One year is not a long period for the fertilizers to go bad. Was it exposed to light or heat? If not, you can safely use it. Do not dissolve it in water though. The granular fertilizers are supposed to work slowly.