I’ve heard all the remedies, and there are a lot out there. Some of them work and some don’t. Some may help, but not one is the solution. But like almost anything else, if you understand moss and why it grows, the solution gets a lot easier.
Moss likes to grow in shady areas that tend to hold water longer than the rest of the lawn. That’s why you usually see it growing under trees or where the soil is more compacted. These are also the areas that the grass has a hard time growing. Yes, it likes acidic soils but it will grow in neutral soil as well. This is why lime will help but it won’t be the solution. Moss killer works well at killing the moss but it really does not cure the situation; it just gets rid of the moss so you can get to a good point to start over and work to prevent it from coming back.
If you’re under a big oak tree and you get less than 3 hours of good filtered sun and you have tried seeding and the grass just won’t grow there, then it’s time for a nice clean layer of mulch around the base. You’re in root competition between the grass and the tree… and the tree will always win. But if you’re in that same area and the grass just slowly gives up and the moss slowly takes over, then there is a solution.
What you have to do is give your grass a fighting chance. You see, moss, if given the chance will matte out over the grass and smother it, but if your turf is growing thick and vigorous it will smother the moss. So if you can keep healthy turf growing and mow it a little higher than normal it will choke out the moss. If you have a sprinkler system and you’re watering the same amount in the full sun areas as in the shade, this will make the shady areas more favorable to moss growth. Moss likes those moist areas that don’t dry out till late in the day.
Moss Max by Bonide - This fast-acting herbicide (available in a spreadable granular form or water-based spray), kills moss, algae and lichens on lawns, trees, roofs, decks, patios, buildings, fences, walkways—all without damage to desirable plants. It contains no fertilizer, so there's no excess grass growth and it's easy to apply with lawn spreaders. The granules turn the lawn deep green and remove any green slime. In lawns, you'll see the best results when you use this in conjunction with good cultural practices mentioned above.