Completely New Need Help

All my friends have grown for years and i just started my first plant about 2 weeks ago so far so good. I'm doing it indoors due to the time of season it is and where I live an outdoor guy would be difficult to hide. Anyway I really just wanted to know when I should start cutting light back and getting the flowering started and also wanted to ask if there is any truth to what ive heard about strengthening the stem by using a fan (I woke up to my plant almost completely toppled over this morn.) Im actually quite familiar wit gardening used to work in a greenhouse but have no experience with marijauna plants so Im just trying to do everything the right way but also in a simple way.

a slight breeze will strengthen stem, and provide adequate ventilation to your plant. you should switch your timer to 12/12 when you see preflowers on your plant or a good size (18 inches)

Flowering depends on the size of area you have and how big of a plant you want, if you have a 6.5 foot area you can start flowering at 18"

and yes a fan will make the stem stronger, it will make the plant think it lives in a windy area and needs to beef up a bit to survive,

Are your lights too far away? This will cause the plant to grow up towards the light and eventually fall due to the weak stem.

Most people veg the plant for 4-6 weeks. When you switch to 12/12 your plant will grow explosively and may double or more in size. If we knew the strain we might be able to find out how much it grows, or at least a ball park.

Not only do you need a fan to strengthen your plants, but as your plant breaths through the stomata, it inhales carbon and exhales oxygen. If there is no air circulation, your plant will suffocate, as oxygen does it no good on the top side. Another reason for a fan is to break up the heat traveling off your lights to your plants. Heat = bad.

I actually did have the light a bit further away than I probably should have moving it closer was the first thing I did. As for ventilation it has plenty of that without the fan but I added a fan to it as well. I dont know scientifically what strand it is but its from some BC's and the other one I have is a purple haze seed. I have somewhat limited space and Ive heard that you can make the plant stay short by forcing flowering when its still short. Right now its about 8" tall after 12 days but I also heard that you shouldnt flower til the nodes (not sure about that term, but the leaf stems that grow off the main stem is what I mean) alternate on the main stem. Is there any truth to anything Im saying here? most of the info i have is just from searching all over the internet and ya know how that goes. Im hoping to keep my plant under 4ft if possible I really dont care how much I yield on this first one its more to get my foot in the door and gain some experience. I really apreciate all the help too, this site and you guys all rock!

You can run 12/12 from the moment you plant the seed. Some growers do. It's generaly thought that the plant does best if you wait till it matures, i.e. shows preflowers and alternating nodes, but many growers disagree and get great results. So it's not a big issue. Flower when it suits you.

When you switch to 12/12 the plant goes through a phase called the 'stretch' where it grows rapidly increasing it's size to 1.5x or even as much as 3x it's size when 12/12 was started. How much exactly depends on the strain. You need to look it up. If you don't have that info then you have to be conservative.

If plant does get too tall, there are training and topping techniques to control the canopy.

Good luck with your grow.

if you plant fell over it might of stretched if so just bury the stem up to the leaves or pretty close and it should be good form there
all plants strech when they first start growing and if the light is kinda far away

awesome thanks again for all the help. i buried it up on the stem a bit and added a fan also moved the light source closer, I think I need a better light source now that its getting big though, clearly the light I have has worked thus far because its grown perfectly fine up til now, but I keep seeing ppl using a much a more powerful light than I do, I have just a regular 60watt bulb in a fixture that has like a reflective bowl around it so it reflects a ton of light but again i see ppl talking about cfls and 400 something or others so i might need to invest in a better light when I switch to 12/12. also if my room is completely dark at night do I need to seal up the plant in a closet or a box of some type. I was gonna build a 6' x 4' x 4' box and seal off all the light and ventilate it with fans do i need to go to all that trouble if my room is devoid of light for at least 12hrs?

yeah you might want to get some cfls atleast to put your plant under they will help alot more then the 60 watt get 6500k (daylight) for vegging and then the 2700(cool light) for flowering the plant uses the different light spectrums for flowering and veg. you dont need alot of them i have three 23w cfls over mine right now but i only had 2 before and it grew fine. you could be fine with out a box but if light does get to the plant when it is flowering it can really mess it up and it wont flower as well or might not.