Moss has leaves that may be only one cell thick and moss plants have no roots, so water hydration for moss is primarily through itsleaves. The primitive anchoring rhizoids of mosses will wick some moisture and then transfer it from cell to cell but moss has no vascular tissues or roots thus moss has no water storage capabilities either.

Almost all moss species require rainwater, or if not available then distilled water. Tap water is usually "hard", meaning it leaves a scum if evaporated, is not acceptable for moss. If you have a water softener your water might be "soft" but it will contain too much salt or sodium ions. George Schenk in his book Moss Gardening mentions almost nothing about this but his residences around the globe were all in places that receive tremendous amounts of rain. Michael Fletcher of Britain in his book, the Moss GrowerÂs Handbook, however is very explicit in this water requirement that it be rainwater or distilled if rainwater is unavailable. (MichaelÂs book is based on fifty years of growing hundreds of different moss species and liverworts). I consider surface waters, such as ponds, rivers and lakes, as also probably acceptable. There are some mosses that grow on limestone and thus may tolerate "hard" tap water but they are the exception rather than the rule. You may not want to water your moss and that is fine but if you do water it must be rainwater or distilled or as mentioned above.

Since moss has no roots or vascular tissue, moss grows only up to four inches max with most species below one or half an inch. Moss small stature means moss has minimal watering requirements. Water your moss with a sprayer, not a watering can. Water applied with a sprayer, squeeze or pump, every three to four days can keep five square feet of moss looking great for a month during the hot summer with no other water source and use less than a gallon of water. Again, you do not have to water moss outdoors. Only if you are transplanting moss outdoors in the Spring or Summer or if you are growing moss in containers indoors.

Mist or spray and then come back a few minutes later and mist again. Try to apply enough to wet the top half inch of soil as well.

Try collecting rainwater and store in gallon jugs.

During periods of time that moss will be moist and growing you can fertilize by applying acid loving plants fertilizer at ¼ the strength mentioned for most plants and only every two to four weeks. I have used miracle gro acid fertilizer and peters acid fertilizer. DO NOT USE ANY REGULAR FERTILIZER which usually contains calcium and or zinc. I was watering a hanging basket of coleus and million bells with a mix of rainwater and regular miracle gro fertilizer. Under the basket but not directly underneath I had some green sidewalk moss, B. caespiticium, in a large clay saucer. Some of the regular miracle gro solution dripped from above onto half the moss in the saucer below. Within five days all the moss was dead that had been moistened by regular miracle gro. Each and every little tiny moss plant!

Using water absorbing crystals, such as hortasorb, in small plantings was recommended by Schenk and I certainly agree. More on water crystals in Moss FAQs: Soil.

Rick