They are often plants from more tropical parts of the world and require temperatures similar to what we consider comfortable. Certain plants require more light than others do. Humidity is important because we often use dry heat to warm our houses. This low humidity will limit our houseplant choices, because some houseplants are used to the high humidity of the jungle or the greenhouses where they are commercially grown. Knowing the light and humidity available inside an area of your home where you would like to put a plant and choosing an appropriate type of plant for these conditions will greatly increase your chances for success.
Humidity is a little trickier, but it is safe to say that most homes have low humidity indoors.
Feeding houseplants can also be done with natural materials without driving your domestic pets crazy or making the entire house smell like a freshly manured farm. There are several products that will feed your houseplants very effectively without stinking up the joint. One of my favorites is a tea made from fully decomposed compost or worm castings. I make it by putting about a half a cup of compost or castings in an old nylon stocking and put it into a gallon bucket of water. If you are not inclined to take the time to make this concoction there are some ready to use materials available that work very well.