There's no rule, but expect if to be unsafe/unreliable after some months by caution.
Store in a closed container, preferably without air, in the dark and at cool temperatures, around 15°C is a good idea. Cold and warm, oxygen and light are the first elements to breakdown/transform the active components.
Any product making a precipitate during storage, changing color or smell, is to be considered going the wrong way and should not be used and be disposed of in an adequate place for destruction, that is a pesticide collection program, and then destructed in incinerators tailored for. Do not ever empty them in nature, you backyard or your plants, nor into a river. You don't necessarily know how long they will arm the environment then, plus most are killers for a lot of life out there, from the soil micro-fauna to aquatic animals, not to mention beneficial animals mushrooms and weeds you may have in the area.
Just to give an example, I've tested once an out of date (really) insecticide for mealies. It did not kill them, but sure it smelled even worse than it did before and the next bunch of leaves of the african violet were all weird. Imagine on your 'kids.
|