What are two parts to a controlled experiment

You can control time in a experiment EX: say you let a plant sit in the sun for 5 hours and then let another plant sit for an entire full 24 hours and see what's the effect well what you controlled there was the time and your dependent variable would be what ever happened to that plant.  so you can control time and you can control speed if its an object that acquires you to exert force. 

Ithink its false. hope this : )