Leaving one female to open pollinate with a selected male gives you enough seed for several seasons at no cost. Quality depends entirely on parent selection, and the home breeding notes at https://calmcbdseeds.com (https://calmcbdseeds.com) explain how to isolate a pollinated plant from the rest of a garden. Expect wide variation in the offspring. It works well for outdoor growers who plant dozens and simply cull anything that underperforms.