It definitely works as long as you cover the whole plant. I grow entirely in Aeroponics so there is nowhere for anything to hide. If I run h202 at 8ml per litre in the aero and spray the plant completely with the starch solution, no pest or disease survives, at all. It’s pretty cheap and available in any supermarket, harmless to people plants and the environment.
i'll be out shopping this morning... just started a new grow... but b4 putting the plants in the tent, i bombed with dr doom, sprayed everything down with bleach n then avid, then left a no pest strip in the tent for 5days b4 finally bombing once again... this weekend i will treat my plants to a pasta water dinner....