I want to check on best used by dates, best shelf life, temperature concerns for storage

Question

I have many containers of fungicides, insecticides and fertilizers, both liquid and granules. I store them during the winter in a garage that does not get colder than freezing when it is 0 outside. I want to know how effective the chemicals I have are. A rose friend told me to discard liquid chemicals that were left on my back porch last December but that the granular products should be OK. Thanks for any advice.

Answer 1

The publications below say it's best not to store pesticides more than two years.

https://www.gardeningknowhow.com/plant-problems/pests/pesticides/shelf-life-for-pesticides-and-herbicides.htm

http://psep.cce.cornell.edu/facts-slides-self/facts/gen-peapp-shelf-life.aspx