This is for Melinda--and anyone else who is interested.
My formula for growing healthy houseplants is to give them light, water them thoroughly once a week, and feed them with Miracle-Gro monthly. Of the 3, watering is the most important.
I believe improper watering is the major reason why people have difficulty raising houseplants. There are two things to consider in watering--frequency and amount. Most plants should not be watered more than once a week. This allows the soil to dry out between waterings. I have read that if you stick your finger in the soil for an inch or two, and dirt clings to it, the plant does not yet need water. Therefore it is sometimes longer than a week before I water some of my plants. The exception would be my ferns. They seem to need more frequent waterings--probably about every 4 or 5 days. It is much better to underwater plants than to overwater them.
The second problem some have in caring for plants is to know how much water to give each plant. The answer to that is that a plant should be watered thoroughly. (This applies to garden plants as well.) Watering thoroughly means giving each plant enough water to evenly wet the soil throughout the pot. This is very important. I have found that many people water their plants a little each day, which causes the soil to always stay moist. That promotes root rot. The soil needs to dry out between waterings. Sometimes people follow the rule about not watering too often, but they fail to give them enough water at each watering to thoroughly wet the soil. If this happens the roots at the bottom never get enough water which stresses the plant and causes it not to flourish.
Another problem I have seen in trying to determine the amount of water to give your houseplants is that one of the rules for watering is to water until the water runs out the bottom of the pot. This may not always be a good indicator because sometimes the soil has dried out so much between waterings that it can't absorb the water quickly enough before it runs out. If this happens, it is advisable to water again the next day--or a couple of hours later so that the soil is thoroughly moist.
I hope this answers your questions. If not let me know and I'll try again.