Hello fellow readers, To lime or not to lime lawns, that was the question from Craig of Andover, NJ. His brother, Chris of Blairstown, then asked if there was a moss killer he could use. True, there seems to be a routine among perfect lawn enthusiasts to lime every spring and fall without knowing their soil’s pH. And rumor has it spreading lime kills Moss.
Expert resources such as Washington State University and the University of Connecticut confirm that lime does not kill Moss. And Moss does not kill lawns; it’s a sign of unfavorable growing conditions for grass, such as shade, poor drainage, poor fertility, or compacted soil.
If your lawn is soggy, try improving its ability to drain by re-grading or installing drainage below the surface. Aerating and dethatching can help too. Herbicides and chemical controls have only a short-term effect. To eliminate Moss, it must be removed, loose soil added, and sow grass seed to encourage a thick turf. Even so, if the conditions that favor Moss are not changed, it will recover over time.
Most Moss prefers acidic soil, while grass thrives in neutral soil ranging from a 6.5 to 7 pH. Therefore, lime added to acidic soil can make conditions less hospitable to Moss. But lime does not constitute a foolproof method of moss control. In fact, in alkaline soils, applying lime may increase the presence of Moss. Always test the pH of your soil before adding anything to it. A pH below 6 is acidic, and above 7 is alkaline. Lime can be effective for acidic soils with pH levels of 5.5 or below.
Rather than engaging in the Moss versus grass competition, a Mary method is to plant plants that thrive in shaded areas to prevent Moss from growing there. Perennials such as astilbe, brunnera, heuchera, hellebore, pulmonaria, and ferns come to mind – all with good deer resistance.
What do Craig and Chris have against Moss anyway? It’s green, lush, comfy on bare feet, and doesn’t require cutting. Thank goodness I have won over their brother Curt to leave well enough alone where a blanket of moss carpets the brook’s bank. As nature intended.
Column Updated 4/8/23
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