I have white widow frem the details say 9 weeks I have a dwc in a grow tent that is 4)(3)(5 useing cfls for one girl I have (4) 45 watt on here just want to know how long do I let her flower for in
White widow will go a little longer than 9 weeks because it is an hybrid ( 1-2 week longer) REMEMBER NOT TO COUNT THE PRE-FLOWER STAGE OF GROWTH AFTER SWITCHING TO 12/12 (pre-flower stage is 1-2 weeks long - which is the time it takes the plant to start producing bud site)
You monitor the Trichomes. Only by determining at what level of maturity indicated by color. You need to see some % of amber Trichomes on your buds to start the process of flushing the plant and harvesting.
Search "Trichomes % here at ILGM forum and I believe you will find many explanations of my answer. Peace