Captain Jack's Deadbug Brew killed my plants
We had an incident in our garden recently where the use of Captain Jack's Deadbug Brew killed all the plants on which it was sprayed. This is an organic pesticide that contains Spinosad. Searching google, I can't find any other incidents of this occurring, so I thought I'd ask here if anyone knows how this might be possible.
This same bottle of Captain Jack's has been used by our gardener for the past year, and sprayed on the same plants without incident. It has been stored under a wooden bench on our roof deck in a moderate climate (San Francisco). We did have a few cold days in Jan where the temperature got down to the 30s, so there is a possibility that the near freezing temperature had an effect.
The garden is mostly succulents and passiflora. We use the Captain Jack's to manage a spider mites problem. Within a day of the last spraying I noticed that all the succulents had turned white and spongy, and the passiflora leaves were brown. After a week, all these plants were completely dead. Other areas that were not sprayed were perfectly fine.
I don't know if this stuff can go bad, but it certainly seems like it has. The color of the liquid in the bad bottle is slightly brownish yellow and has a slight odor, whereas a new bottle is clear and has no odor at all. We're pretty sure that no one has tampered with the bottle or put anything else in it. No one has access to our deck but us.
I'd really appreciate any insight anyone might have on this problem. Thank you!