Fast versions are created by crossing a photoperiod strain with an autoflowering relative and then selecting offspring that keep light dependence but inherit a shorter bloom. Most fast flowering weed seeds for sale finish roughly one to two weeks sooner than the original photoperiod parent, typically wrapping up in six to seven weeks after the light switch. Unlike autoflowers, they still respond to a twelve-hour schedule and can be kept in veg indefinitely. The result combines flexibility with speed.