Question
I bought a cymbidium orchid and a small phalaenopsis orchid about 3 weeks ago, and all of the flowers have fallen off both. The cymbidium leaves are also turning brown at the top. The phalaenopsis is orange and red with no flowers and the leaves a light green. I have them both in mild sun and water with a 30-10-10 feed once a week. What am I doing wrong?

Answer
Amanda, Let's first discuss the cymbidium.  Most cymbidiums are cool growers and, I'm assuming that you live in a climate that can be quite hot. The best way to grow cymbidiums in Texas is in a greenhouse where temperature and humidity can be controlled. Cymbidium leaves can become overheated in direct sun and can "burn".  This is seen when the upper side of the leaves turn brown. You need to provide at least partial shade to keep the plant cooler-- that should prevent leaf burn. Unfortunately, most mass marketers of orchids are not concerned about repeat business as would a local orchid grower.  The result is that these orchids are marketed for short term sales success and not to help the new owner with long term success.  Usually, the plants are in old potting mix that leads to root rot or they are sold in tightly packed moss== both of which can lead to root problems.  You cannot correct the damage that has already happened,but, in addition to the cooler growing conditions, I suggest that you promote new growth by repotting the cymbidium in an orchid potting mix (not moss-based) in a pot with lots of drainage holes. Once new growth gets to be several inches high you can water and feed it several times a week.  Try to avoid using water with high salt content.

You didn't mention how long you have had the phalaenopsis but I will assume that you purchased it this year in flower. Most phalaenopsis flower once per year and usually in the spring.  Light green is a good leaf color and suggests that it is getting the right amount of light for flowering. Repotting the plant in a good orchid potting mix is probably also a good idea for this plant.  As with the cymdidium avoid moss-based potting mixes and use a pot with lots of drainage holes. Best temperatures for phalaenopsis growing is 65-85 degrees but, too bright of a light, can raise leaf temperatures and cause leaf burning.  Phalaenopsis prefer lower light levels than cymbidiums and prefer the more constant temperatures inside-- preferably in an east window.