Why Is My Moss Turning Brown?

Moss, a dense, low-growing, nonflowering plant, forms a carpetlike mat that grows over top of rocks, trees and soil in your garden. Mosses require some care to thrive or you are likely to see problems, such a drying and browning. Fortunately, mosses are adaptable and easy to grow, making this problem is easily remedied.

Most mosses thrive in moist to damp environments with plenty of water. Without the proper moisture, moss begins to dry and turn brown. Moss turning brown due to lack of water is quickly fixed. Once given enough water, the moss becomes lush and green once again. For this reason, it is important understand the water needs for the specific species of moss growing in your garden. During periods of drought and low rainfall, water your moisture-loving mosses.

It is not enough to provide your moss with the right amount of water. The quality of the water also plays a part in its health. Moss uses water as a source of nutrients. If you notice your moss turning brown, drying out or dying, it is important to look at what type of water it's getting. Moss is sensitive to certain minerals in tap and hose water, such as calcium. Too much calcium can injure mosses. Only water your moss with distilled water or natural rainwater.

Rainwater may cause your moss to turn brown if it is contaminated with chemicals from pesticides and herbicides. For example, if you've used chemicals to dry out and remove moss from other parts of your yard, it may affect the mosses you want to grow. Flush the soil around your moss plant with clean water if you suspect herbicide damage. Problems from tainted runoff are only likely to continue in periods of drought. Once the moss is getting clean water again, it should turn a healthy green.

Providing moss with the right care is essential to avoid drying, browning and other potential problems. Too much sun causes browning and drying and the breakdown of the plant’s food source -- its chlorophyll. Most moss species require partial to full shade. Mosses also thrive in acidic soils. Do not apply fertilizer to moss because it can burn the moss and turn it brown. Be careful when using fertilizer on nearby garden plants that it doesn't touch the moss. Moss can also turn brown when continually walked on or stamped down by pets. Keep your moss out of areas where people walk and pets play. Most importantly, know the species of moss that you are growing and provide the appropriate care.

If you are providing the proper care and your moss is still browning and suffering from problems, ask yourself if what you are growing is a true moss. Irish moss (Sagina subulata) is a mosslike plant that grows in U.S. Department of Agriculture plant hardiness zones 4 through 8. Although the common name and appearance would suggest this plant is a true moss, it is not. Irish moss is an evergreen perennial, often grown as a pathway plant in between pavers and stepping stones. This plant requires different care from true moss, including full to partial sun and rich, well-draining soil. Browning and drying in Irish moss that's getting the right care may be the result of too much heat from sunlight as it reflects off stones and pavers. Fix this by providing some shade during the heat of the day. When healthy and vibrant, Irish moss produces white flowers in spring.