Phalaenopsis, also known as the Moth Orchid, is the most popular orchid in the USA. It's long lasting sprays of beautiful blooms in a broad array of colors from pure white, yellow, orange to intense pinks make it an attractive plant for every home. They are easy to care for and with a bit of attention and regular watering their flowers will last for weeks and return year after year.

You will find Phalaenopsis at your local flower store, garden or home center. The price range, mostly depending on size, is between $12 and $40. Some rare or award winning plants might cost between $60 and $120. When you buy your plant, make sure it is in good condition. The leafs should be of a medium olive green, smooth and shiny. If they are yellowish and leathery structured this might be a sign that the plant has suffered dryness and there is a risk that it will loose the blossoms.

Light
Phalaenopsis likes medium light, but no direct sun. A west or east facing window with direct sun limited to a few hours is ok. A south facing window with a some shade from trees might work well, too. Without shade a south window will be too bright and the plant will suffer from heat stress.
I use a light meter to measure the light intensity. It will give you a reading of the light intensity either in Lux or Footcandle. For Phalaenopsis orchids a light level between 10,000 and 15,000 Lux or 1,000 and 1,500 Footcandle is recommended.

Temperature
Most Phalaenopsis do well in normal indoor temperatures. They like 70 to 85 F during the day and 60 to 70 F during the night. What they do not like is too much dry heat, for example near a radiant heater or in a south window. Also avoid cold air fom AC units or ducts. In colder climates like Minnesota there is a risk from cold air intrusion through window cracks or from the cold glass. Check frequently and use a window insulation kit if necessary.

Water
The potting media should seldom dry out. If you look at the media you will find that it is mostly made from chuncks of barch, vulcanic rock, styrofoam and some moss. All these materials allow a lot of air to come to the orchid roots. But most of these materials do not absorb and store a lot of water. The best watering method I have found is to submerge the orchid pot in a bowl of water for 15 minutes and then to take it out and let the excess water run off. Watering frequency depends on the temperature and humidity in your house, but once or twice a week should be suffcient. In many loactions tap water contains a lot of minerals and is not recommended for orchid watering. Use clean rain water, filtered drinking water or distilled water instead. Also be careful if you have a house water softening unit installed, some of them put a lot of sodium in the water and orchids do not like that.
You can use a "TDS meter" to measure the mineral content of your water. The reading for water without fertilizer should be below 10 ppm.

Humidity
The best humidity range for Phalaenopsis is between 60 and 70 % relative humidity, but with regular watering they will tolerate lower humidity. To create a better microclimate you can also place trays with moistened pebbles around your plants. They also like to be sprayed with destilled water on a daily basis, but make sure that there is no water in the center of the leafs, since that may promote rot.

Fertilizer
Since the potting media contains little nutrients, a weekly fertilizing with dilluted fertilizer is recommended. In most cases a balanced 10-10-10 or 12-12-12 fertilizer at one quarter to one half of the manufacturers recommended strength works well. I usually fertilize for 3 or 4 weeks in a row and then do one submerged watering with clean water without fertilizer. This will flush excess minerals and nutrients away and will prevent an unhealthy build-up of excess nutrients.

Potting
You should repot your Moth Orchid every one or two years, before the potting media breaks down or accumulates too much minerals. The best time to do this is right after the flowering. More details in the potting section.