I had just about given up on growing moss until I started using bird netting to keep debris and animals out. One myth I’m still not sure about, is if tap water kills moss.
Last year I watered a lot, with no net and the results were not very good. This year I am letting my moss dry out and keeping a net on it and it is doing much better, but I’m not sure of how harmful tap water is, and if I should think about watering it.
We recommend using rainwater for the best results, you can also age your tap water to reduce the chloramines. Tap water is different for each city and we can’t speak for each one; however our experience in North Carolina has been that tap water is fine to use straight from the hose, without detriment to the mosses.
We have achieved superior results in vitality with higher quality water sources like harvested rainwater, so water chemistry does matter. Pay attention to volume, frequency, and time of day, as well for the optimum results. Drenching can lead to problems, frequent misting is better. Watering in the morning or afternoon is better than in the evening. Depending on the species your growing, regular drying out may be required for long-term health. Avoid creating a constant wet then dry cycle over the course of hot summer days. It’s better to keep moist all day, then dry all day, this avoids having the moss go into dormancy multiple times in a 24 hour period which uses as much energy as it produces, resulting in a net loss for the mosses growth.
Good luck and let us know how you make out.
Moss And Stone Gardens