By Jensen
Oxfordshire,
United Kingdom 
How long do things like weedkiller, Bone Meal and Fish Blood last? The same question also for: Tomato Feed, slug pellets? I have a friend who moved four years ago, and left all of this in the garden shed. All the items have been opened before and used, although some of the weedkiller is in unopened sachets. The items were of course all packed up/closed again after being used. I would like to point out that I do not use weedkiller or slug pellets, as I prefer better ways to counter these problems,
Thanks.
13 Jul, 2011
Answers
I would not use them after 4 years, they do have a shelf life and they are chemicals.
13 Jul, 2011
I agree with Drc the ingredients will have degraded.
14 Jul, 2011
Thanks for all your replies.
14 Jul, 2011
Fertilizers are usually good as long as they are dry, though with the organic ones, things feeding on them may change the analysis and speed of action a little. I wouldn't use any other garden chemical stored outside after the first year, though our extreme heat tends to burn some things out quite fast. Stored indoors, no longer than three years for most, and no more than a year for Malathion.
15 Jul, 2011
Previous question
« What kind of plants would you use in big pots for a natural looking garden?
We had a third of a bottle of Murphy's Sluggitt which was years out of date, so much so that instead of being liquid, it had gone solid in the bottom of the bottle (you normally add a measured liquid dose to a watering can). We added water, shook it a good while, then used it. It was still effective as was evidenced by the dead snails. So I would think you should be OK if the packs and bottles are still sealed.
13 Jul, 2011