I have a few orchids inside my place. Most are Phalaenopsis, and one vanilla orchid. After talking with one orchid grower, they told me the key thing when taking care of orchids are:
* Do not overwater them (no standing water on the base of the planter). Keep the media moist.
* When the root turned white, give them water until they turned back to green (apparently they also photosynthesize).
I also have big gardenia in my kitchen and small gardenia propagated from the big gardenia that I put on my work desk.