The technic to control the flowering is called light deprivation.... . The techinc means you give your plant earlier darkness, than the sun does. You can do it like... having your plant in pots, and take them inside after 12 hours, and back in the morning.... in the meantime they stand in a dark place. Or you have a growingtent, that you an close. Big mj "factories" build long tunnels for their weed, and in early evening they give darkness to their plants. This way they can harvest 2 times a year outdoors. Iam looking for pictures and add them in the comments