Can tap water be used for orchids?
Written by
Julia Anderson
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.The quality of water has a direct impact on an orchid's health and longevity. Tap water contains minerals and other substances that can accumulate in potting media over time. As an orchid specialist, I have seen hundreds of plants (including my own) that have been hurt through salt accumulation. Your choices of water will drastically affect the root's function and ability to absorb nutrients.
Tap Water Issues
- High mineral content causes leaf tip burn and yellowing
- Chlorine and fluoride damage beneficial root microorganisms
- Salt buildup reduces media drainage and aeration over time
- Flushing pots monthly reduces but doesn't eliminate damage
Alternative Water Sources
- Rainwater provides ideal pH balance and mineral content
- Distilled water lacks minerals but requires fertilizer adjustments
- Reverse osmosis filtration removes 95% of harmful minerals
- Well water needs testing for excessive calcium or iron
Softened Water Dangers
- Sodium exchange process creates toxic salt concentrations
- Damages root membranes reducing water absorption capacity
- Causes irreversible root die-off within 2-3 months
- Never use even for flushing purposes
Avoid mineral buildup by properly flushing the growing medium. Once each month, run a large volume of water through the pots. I use about three times the volume of the pot itself. I have barrels to collect rainwater for flushing, and it works better than city water. If you flush them regularly, your orchids will thank you with beautiful leaves and blooms when watered properly.
Temperature is just as important as the quality of the water that you are using. Always use room-temperature water. Cold water exposes a tropical root to a shock. I usually put my water into containers and leave them overnight before using it. You can check the temperature with your wrist, just like you test baby formula. Using a proper method means less stress on the root.
Read the full article: 10 Essential Tips on How to Care for Orchids
