time???

ok,

so how much time from the first sign of preflower do you have to get any males out before they would affect any females?????

i ask because out of my 9 i am sure about one female and am questioning 3 to 4 and the rest show nothing.....????

i have been looking at all the pictures on here and they are very good but im not sure how long before it is obvious, and or too late

any help or opinions would be awesome

thanks