Rainwater and Steam Distilled Water

[Leafmite]

The problem with distilled water is it does not have any minerals and most fertilizers expect you to be using tap water so they do not have these minerals or enough of these minerals. Rain water actually collects stuff from the air (The water I collect during a rain is pretty dirty). Most orchids grow where there are either many critters or pockets of decaying leaves and so the plants get the nutrients that they need.

When I switched from Pond water (ornamental pond, filled with both tap and rain water) to distilled water, for the first time, I experienced Calcium deficiency...in a huge way. I call it the 'Black Death' because I lost so many really great Cattleyas and a few other orchids. I used a fertilizer for orchids but I did not know that it was not complete, that it expected the water used with it to have minerals. Even when I used the MSU for rain water, I still had issues.

I use tap water now for all my plants but the Carnivorous plants. My orchids seem fine with it even though the water is hard, probably because our water contains a nice amount of Calcium.