early flowering stage

OK, so I germinated these seeds aboUT mid April, So these plants are about 3 weeks old. Now I start looking like they are flowering. The time from sunrise to sunset is about 15 and increasing so they shouldn't be going into flowering .

Hi I'm on my day 11 of flowering and I wanted to make my buds turn purple :weed: and I've heard that throwing the plant in a temperature that is about 50 degrees Fahrenheit will cause them to turn purple. My question is at what stage of flowering should I put my plant in a place where's it's...