Answer: Moss can be planted and it will take hold and thrive if conditions are right for it to do so. You would need to collect a small sample or "sod" of moss that is growing in a spot very similar to the one in your garden. Place the sod as soon as possible, press firmly into place, keep it slightly moist, and with luck it will establish itself and even spread.
Another method is to collect a bit of moss, mix it with a live cultured buttermilk and "paint" the slurry on the surface where you want it to grow. Again, keeping the area damp can help it to become established.
In the long run, moss will usually appear naturally if a location is suited to it. This is probably the easiest way of "growing" moss.
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