Orchids are killed by improper watering (usually by overwatering) more likely than by any other practice. Discovering how to properly water orchids is one of the more challenging aspects of growing orchids.
The pot-weighting method of determining when to water is one of the easiest. In this method, you're relying on feel instead of precise weights. Here's what you do:
Thoroughly water the orchid in its pot.
"Weigh" the pot by picking it up.
Now you know how heavy it is when it's saturated with water.
Wait a day or so and "weigh" it again by picking it up.
You'll feel the difference in the weight as the potting material becomes drier.
Repeat Step 3 each day until you judge, by looking at the surface and sticking your finger into the top 1 inch (2.5 cm) or so of the potting material to see if it's damp, that it's time to water.
Keep in mind whether this type of orchid prefers to be on the damp or dry side.
Note what this dry "weight" is.
Now the orchid is ready to be watered thoroughly.
This entire process may sound tedious, but you'll be amazed at how quickly you catch on. And when you do, you'll always know the right time to water. Just lift the pot, note its weight, and you'll have your answer.
If you're still not quite sure about watering, keep the following watering tips in mind:
Grow orchids of the same type, growing medium, pot type, and size in the same area: This strategy will make watering them easier, because they'll have very similar moisture requirements.
Water with warm water: Very cold water can cause root and bud shock, which sets back the plant and slows down its growth.
Always use a water breaker (a water diffuser that you attach to the front of your hose to soften the flow of water): For only a few orchids, a sprinkling can with a long spout with a rose (a water diffuser placed on the end of the water-can spout) that has many small holes works well. These devices allow thorough watering without washing out the potting material.
When you water, water thoroughly: The water should pour out from the bottom of the pot. This method of watering ensures that the potting material is saturated and flushes out any excessive fertilizer salts.
Never let the pots of orchids sit in water for over a few hours: If the orchid pots have saucers, make sure to keep them free of water. Excess standing water will prematurely rot the media and roots and will be a source of accumulating fertilizer salts and pathogens (disease-causing organisms, like bacteria, fungi, or viruses).
Water the orchids early in the day or afternoon: That way, the foliage will have plenty of time to dry off before nightfall. Wet foliage in the evening is an invitation for disease.
