Temperature
Orchids such as phalaenopsis, dendrobiums and Oncidiums will adapt to normal temperatures of 70 to 90 F during the day and 60 to 70 F at night.
Light
Phalaenopsis are one of the most tolerant of lower-light conditions. Other orchids will probably require more light to flower freely. Orchids can be divided into three groups based on their light needs: low (an east-facing window), medium (a well-lit west- or shaded south-facing window) and high (south-facing window). The most frequent reason orchids do not flower is lack of light
Water
Most orchids benefit (but not all) from a thorough watering and allowing the growing medium to dry out a little between waterings. Several minutes of watering in a sink with water flushing freely through the medium is ideal. Remember, watering too frequently is the most common reason orchids die.
Humidity
Orchids grow best with at least 50 percent humidity. That’s one reason Florida is such an ideal place to grow orchids—one more thing we don’t have to worry
Fertilizer
Most orchids should be fertilized weakly, weekly. Always fertilize at half the recommended strength for houseplants. A 20-20-20 (nitrogen-phosphorous-potassium) formula works well with most orchids. Over fertilizing is the second most common reason that orchid plants die.
