This is from an extended article I have been working on It explains my views on Cannabis genetics based on my experience.
There are so many ways to cultivate cannabis, whatever your method of starting seeds and growing out plants will work just fine. The important thing is to take clones from all of the plants keeping these copies healthy and in the vegetative state without messing up any labels. In the old days my labeling was suspect which led to some pretty amazing plants that were simply labeled you UNK meaning unknown. Now I don't care who seed you are growing out hermaphroditism is the dominant state of cannabis so while we are flowering the plants we want to make sure to watch for signs of this. A large percentage of amazing strains will try to reproduce himself late late in flower producing one or two single male statements in order to try to make seeds nature always tries to re-create itself. What I am talking about however is not this but something different, any plant that shows signs of duel sex any time before week six should be discarded in and a clone discarded along with it.
During the flowering phase of the grow take your time and inspect the new plants every few days, note the smells as the plants matures, how much the plant stretches. You are looking for the one female plant that matches not only your medical needs but also your growing style. I once threw out a Kali Mist X Blue Widow from seed that was incredible pot but we flowered it the plant would stretch four times its normal height and the plant is wasn't manageable and my grow room. I hated to give her up but this is the type of thing to look for. If the strain your growing out is very stable like our Vortex then the only thing you're looking for is your favorite plant based on smell taste and affect. I have collected my entire garden using this method. Our Apollo-13 mother plant came from seed as did all of our breeding moms at one point in time. Sometimes however it is not easy to find the best female plant in the strain, for instance Simon the breeder for Serious Seeds says that as many as 100 AK-47s seeds need to be started in order to find the infamous "cherry cutting".
Regardless of what the advertisements indicate cannabis seeds are unlike tomato or cucumber seeds. Even the breeder that I consider to be the best in the business only promises 70% stability and that's just a marketing claim he has a nicely proved it to anyone but he certainly has the reputation to back it up I am talking about Shanti Babba. Most of the more famous cannabis seeds for sale in the market today like super Silver Haze, White Widow, and even Jack Herer have a tremendous amount of variation in sometimes a keeper female cannot be found in the single 10 pack. This is the stark reality of cannabis seeds that no one wants to talk about that as I like to say before I was a breeder I was a grower and I still am. I personally grow out five new strains every year selecting different breeders or different famous strains in order to see if I can find an amazing keeper.