Way to tell if pitcher plant is getting enough food, water, and sun?

Is there a way to tell if a Sarracenia pitcher plant is getting too much or too little of light, water, or food? The pitchers are brownish, and I haven't been feeding them, since the plant is outside. I assumed it was getting enough. I do not believe that the pitchers have grown to their full abilities. They are still closed, in a way, and do not have the collar type things sticking up from the back of the pitcher. I was wondering if I am not taking care of my plant properly. The reasons I came up with were too much or not enough: water (both in the bog habitat and from raining), food (since I trusted the plant to attract its own meals), and light.