Question: I am concerned about Cloramines in water. I’ve heard that these cannot be boiled away and, over time, will cause toxicity in the plant and damage the leaves. I use tap water that I boil and let sit at room temperature. The other alternative I could personally use is collecting rain water and straining that as well as boiling it–I do have a rain barrel.
Answer: We’ll begin this answer like we do many others–if what you’re doing now is working, don’t change it and don’t worry about it. For my first 20 years growing violets, I used municipal water out of the tap (yes, they added chloramines), with little consequence. For the next 20, we’ve used well water (with no additives). Given the choice, I’d return to municipal water in heartbeat!
This is not to say that chloramine is of no concern–just not greater than any number of others faced by the grower. Chloramine is a chemical compound (or ammonia and chlorine) added in low concentrations as a disinfectant to municipal water, as an alternative to “free” chlorine. It has been used by municipal water systems for many decades. Its used is becoming more widespread, wince it is more stable than chlorine and does not dissipate from the water before reaching users. Precisely because it does not easily dissipate, it is likely to remain in the water when used on your plants. Unlike chlorine, you cannot “age” your water, leaving it out in open containers for a day or two, until the chlorine has left the water. Chloramine also cannot be removed fro the water by boiling, distilling, or reverse-osmosis filtration. According to the EPA, the best means of removing chloramine is by use of an activated carbon system–a quality, granulated, activated filter and allowing sufficient contact time with the water being treated. The best of those multistage systems can remove nearly all of the chloramines (as well as most other contaminants).
After all of this “scary” stuff, why not be concerned? First, unless your municipal water authority is negligent and using chloramines above recommended levels, it should be harmless for both you and your plants. Second, to the extent that you might be concerned about cumulative effects on your plants, this is only an issue if other good cultural practices are absent. One of these is regular repotting of your plants. Violets, and most other plants, should be repotted at least once per year, better every six months. By refreshing soil regularly, you will be removing much of the contaminants in the soil, such as chloramines, fertilizer salts, and the like. If you’re using a constant-watering system, like wicking or self-watering pots, regular refreshing of the soil is a must, since the soil is not “cleansed” as it would be with top watering.