about lighting

my plants are about two weeks old when should i start to cut the light back and how many hours of light do they need a day for a good budding plant

its kinda up to your self how long you veg for depending on how much room you have in your grow and 12 hours light and 12 hours dark this will induce flowering .

what do you prefer

flip the lights to 12/12 after your plant reaches maturity at the earliest. They will show preflowers and the nodes will begin alternating. Depending on the size of your area you may need to do some topping or lst to keep the plant short and bushy, they will approx. double-triple in size from the time you begin flowering if mature to the end of the stretch phase of flowering.
12/12 lighting, absolutely no light leaks or interruptions. None! You dont need to gradually cut the lighting back, in fact it hurts more than help, each of those days it will still be vegging till the cycle gets around 12/12 anyway so you might as well give them all the energy they wouldnt get if you cut back slowly instead of just going to 12/12.

thanks much appreciated