Doesn't COMPLETELY gaurantee it but it most certainly will be female. Also, stressing the plant can have an efffect on the sex.
Try not to go for new strains in my opinion they are produced far to quick and cant not of been properly stressed tested before they work the magic of feminizing.
Thanks, Could you recommend a few strains that I could depend on? As in stuff that will most likely work well...
No, but most likely they will be. Femmed seeds come from hermy plants and there are some people that won't use them because of that. I've had good luck myself and the only (very minor) herm problems I've had came from "normal" seeds so... whatever. Barney's Farm LSD= crazy good weed.