It's been a while with my lemon plant and I have been watering it every day at noon with drinking water. Today while watering I see that some of the leaves, especially at the end of it, is brown in color and very dry like it's dead. I'm not sure what is going on is it because of too much sunlight or not enough water. Please do help. How can I make them go green again? Do I have to chop the leaves off or wait for it to heal itself if such thing can be done?