▁begin ▁when ▁pow der y ▁mil de w ▁sympt oms ▁and ▁signs ▁are ▁first ▁noticed . ▁Con vent ional ▁fung ic ides ▁should ▁be ▁applied ▁on ▁a ▁regular ▁basis ▁for ▁best ▁results ▁against ▁the ▁disease . ▁▁ ▁Control ▁is ▁possible ▁with ▁tri ad ime fon ▁and ▁prop icon az ole . ▁It ▁is ▁also ▁possible ▁with ▁hex acon az ole , ▁my c lob ut an il , ▁and ▁pen con az ole . ▁ ▁Non - con vent ional ▁chemical ▁control ▁ ▁There ▁are ▁some ▁un con vent ional ▁chemical ▁control ▁methods ▁that ▁offer ▁alternative ▁modes ▁of ▁action . ▁▁ ▁The ▁most ▁effective ▁non - con vent ional ▁methods ▁of ▁chemical ▁control ▁against ▁pow der y ▁mil de w ▁are ▁milk , ▁natural ▁sul fur ▁( S 8 ), ▁pot ass ium ▁b ic ar bon ate , ▁metal ▁sal ts , ▁and ▁o ils . ▁ ▁Metal ▁salt ▁fung ic ides ▁should ▁be ▁applied ▁on ▁a ▁regular ▁basis ▁up ▁until ▁har vest ▁of ▁the ▁host . ▁Sul fur ▁must ▁be ▁applied ▁before ▁the ▁disease ▁has ▁emer ged ▁since ▁it ▁prevents ▁fung i ▁sp ores ▁from ▁germ in ating . ▁Co pper ▁sul f ate ▁is ▁an ▁effective ▁fung ic ide ▁allowed ▁in ▁organ ic ▁far ming , ▁but ▁can ▁cause ▁harm ▁to ▁the ▁host ▁plant . ▁Add ition ▁of ▁l ime ▁h amp ens ▁this ▁effect . ▁▁ ▁Ne em ▁oil ▁effectively ▁man ages ▁pow der y ▁mil de w ▁on ▁many ▁plants ▁by ▁inter fer ing ▁with ▁the ▁fung us