Choppers start looking for patches in mid september in oakland county,other areas may be different.
And FYI liquid copper isnt harsh & its no worse than green cure,one manufacturer says not to use a week before harvest,mainly beacuse they play it safe,now another manufacturer comes along,mainly in the grow shop/ hydroponic relm & says to their coherts how can we distinguish our product from the rest ? Wait i know ! Lets say ours can be used up to the last day before harvest because most mj growers do not research what chemicals do once used they just read lables,if the lable says "all natural" or its in some way safer most growers will use it.
Liquid copper is the shit,i use it on all my grows,indoors & outdoors,on the indoor plants i use it up to the last week of harvest,no taste or quality issues either,its the benchmark product for its use & nothing on the market is as good.