Hey bongzilla, there is not a given time frame on how long you will need to wait. Care to give us some more info on your grow?
1. Soil or Hydro?
2. If hydro what type bubble, ebb and flo, etc.?
3. ferts/nutes used? Soil mix?
4. Lighting: Florous, HPS, MH, or mix? wattages?
5. PH if known?
6. What stage of growth?
7. Relative humidity and temp of area if known?
8. Grow area size and ventilation?
9. Any other measurements that may be useful like PPm, EC, CF, etc.?
10. lighting schedule?
We can go from there...glad to have you on the board.