I have a small patch where I grow onions, tomatoes and garlic. It is mostly a hobby to purge the body of stress of the day to day hustle. I never used pesticide in the past, but the bugs got wise to my little patch of heaven, and has been mowing it down since 2 months ago. On the net it is suggested that you give a healthy dose of pesticide as it grows. Then give a dose once a week and 1 week before harvesting I stop the dosage and just water normally to purge the plant from any toxins.

Is this recommendation correct?