First off, I would like to say that I have well over 30 year of experience with all types of plants, herbs, fruits, vegetables, and virtually everything else that grows from the ground. I am a master of science in plant biology, and my line of specific research is horticulture. Plants are my life. This is most prominent tip you will ever encounter;
People always tell you that you will need a specific lighting schedule to tell your plants what season they are in.
Although this is true, this isn't the only approach;
Your plants can simply tell by how much you are sweating. The reason for this is that humans only sweat in the summer and spring. When you excessively sweat near your plants, they will be more encouraged to grow due to electrical synapses in the plants chloroplast.
This system can be easily abused.
1. Leave your lights on 24 hours a day when flowering.
2. Every 6 hours (this is important) go next to your plants in heavy winter clothing so they think that it's winter time. Spend no more than 18 minutes at a time or else the plants will dismember.
3. Buds (impossible to induce pollen sacs) will start to show by the 2nd day. If it doesn't show, keep trying, it will.
4. Harvest 6 days later. The buds will just grow overnight, but to produce the most THC, it's safe to leave it on an extra 5 days.
Also, you can literally train your plants without stressing them by following this simple routine:
1. Leave your lights on 24 hours a day.
2. Every 8 hours (again, very important) stand next to your plants in either summer clothes, or strip down completely nude. It works best if you are stripped completely nude, but if you don't want to feel crazy you can use the summer clothes (shorts and a t shirt).
3. Wear sunGLASSes, the plants can sense polarized glass which will induce them into a spring fever mode.
4. Again, spend no more than 18 minutes at a time with the plants.
5. In 4-5 days, the plant will start shaking rather violently nonstop. That's okay, its ready to metamorphose. This is a completely normal process and should be overthought.
6. In about a week, the plant will look like it has been trained for years. It'll be like a little bonsai bush.
7. If the plant doesn't train itself, then try to get a sweat running before you go into the plant room.
That's about it. If you guys have any questions, feel free to ask.