Moss-covered (Bryophyta) fireplaces create the illusion of stepping back in time to the days when cooking over the open fire was the norm. Whether you are creating a sanctuary to honor the past or wish to enhance the natural beauty of a stone fireplace in your backyard, covering it with moss will take your backyard to a whole new level. With more than 10,000 species of moss to choose from, at least some species of moss can be found from U.S. Department of Agriculture plant hardiness zones 1 through 12.
Moss usually grows on trees, old logs and stones in moist, shady areas, but it can be found in sunny or partially sunny locations. Look for moss growing in similar lighting as your fireplace receives. Pay close attention to the characteristics you desire when searching for moss. While some moss appears deep green, thick and spongy when grown under trees, other moss appears thin and paler green. The type of moss you gather is the type you will grow.
Making moss slurry from buttermilk and tiny pieces of moss allows you to place the new moss exactly where you want it to grow. Breaking up 2 cups of moss and blending it in the blender with 1 cup of water and 1 cup of buttermilk creates a soupy mixture just right for applying to the stones on your fireplace.
Pouring the moss slurry over wide, flat areas and painting it onto vertical portions of the fireplace sets the stage of growing your own moss. Painting it along curves of the fireplace, between rocks and in random areas creates the best effect. Moss will grow in all areas that are covered with the slurry. Painting the entire fireplace is always an option, but for a natural look, leave some areas bare for the natural beauty of the stone to show through.
Moss may take several months to grow, and some species take up to a year to reach their full height. Keep the surface moist by spraying with the mist attachment on the hose; constant moisture is vital until the moss has become established. Typically, the stones will appear covered in green fuzz as the moss begins to grow. Once established, your moss requires little to no care from you. An occasional misting during hot, dry periods can be beneficial, but it's typically not necessary. If the moss begins to turn yellow or feels dry to the touch, it needs misting.