If you can't see any bugs I wonder what pest you are spraying for? Malathion kills by contact, it doesn't prevent, so there's no point spraying unless there's a visible pest. And it kills everything including bees and other beneficials. It is also toxic in various degrees to fish, aquatic life and birds.

Tbh I wouldn't want it anywhere near my garden. Article on effects of malathion.

It is also an organophosphate type of insecticide.......one that works by disrupting the nervous system. And that can be just as damaging to humans as it is to other mammals and all manner of other animal life. In fact, most other organophosphates have been removed from the marketplace as being unnecessarily toxic. Much like floral, this is substance I would not use in my garden!! Most pest problems can be addressed in a much less toxic manner.

oh my my my I am not going to use it any more. Thank you very much