noob, problem while flowering

hey everyone. I am a noob so i guess thats why im having a problem. Well I switched my girls to flower on April 3rd. A week after, i got white hairs. Well i have 4 white widows in soil, feeding them all the same nutes, distilled water, ph 6. 400 hps light. 3 of my girls are budding great but one is just getting taller. It has white hairs, but its not budding and they were all switched to 12/12 at the same time. They all get the same amount of light and it just doesnt bud. Why could this be? Thanks in advanced!

unless you know for sure its a female it could be because its a male plant... does it have things that look like little clusters of grapes? if it does its male... if it is just a female it could just be a very slow maturing female... if thats the case just be patient..

I know for sure its a female. I had 8 plants and 4 were boys, i can tell the difference between male and female. The males are easy to tell with balls growing all over. But impositive its a female. It has white hairs all over but no budding. Thanks for your responce and help!