eisnerl
Your question could cover thousands of plants, so you'll have to help us out here. Pictures of plants/problems would certainly be helpful as well as specific plants. Your growing conditions are a must if you want advice on growing houseplants. Did you know that most people don't think they can grow tropical plants, yet 90% of houseplants are tropical plants? For some reason, the very words "tropical plant" makes many people think there is something really special when growing them.