Question
Hi! I have two orchids I recently bought from my local hardware store. They were in a reduced section just because they were done blooming so I decided to take them. One is a phalaenopsis and the other is an oncidium. I was wondering if you could give some basic care tips for these plants as I am new to orchids. Also, both these plants were potted very tightly in sphagnum moss and there roots are coming out of the pot. Would repotting them in new potting soil be okay? Oh, and both plants had flower stalks on them, but the flowers are all gone. Is there anything I can do to the flower stalks to get them to rebloom?

Answer
Victor; you definitely need to repot these plants.  Go to a garden center (eg Home Depot, Lowes,etc) and purchase a bag or orchid potting mix (do not use a soil-like mixture, or moss.
Sift the small particles out of the new orchid potting mix before use.  You probably won't need the whole bag, so save the unused portion as orchids need repotting every spring. After sifting out the small particle, soak the portion of the potting mix you plan to use until you have completed the following steps.

Unpot your plants-- being careful not to damage the roots.  Remove as much of the old potting material from the roots as possible , again, without damaging the roots. For repotting, use a plastic pot with lots of drainage holes and just large enough for the roots.  Remove any roots that have collapsed or are mushy before repotting.  For each plant, insert the roots into the new pot while rotating the pot so the roots lay against the pot sides.  Then, place the wet potting material into the pot in an area where the water can drain out of the pot. The base of the plant should be left just above the potting mix.  Set the plant aside where it can drain for a few days before placing it in your growing area.

Do not remove the old flower spikes because sometimes these can rebloom.

I'm glad you decided to check on the care of these plants as they are not like most other plants. Air needs to get to the roots or they will collapse, hence the potting mix is somewhat coarse.  This is another reason to not leave them in tightly packed moss.