Rich Pasto wrote:water and pH are definitely culprits, but you need to also look at how much sunlight your yard gets. The lower sunlight levels in winter may be helping the moss spread/return every year.
Food for thought, what are the drawbacks to moss beside the cosmetics? You basically dont have to do anything to it, and it will develop into a soft green carpet if left undisturbed. I remember moss yards from back east and they were really quite nice.
Tom Pavlo wrote:It was always my understanding that moss was a sign of your pH being too low. The lime should correct that. A couple of years ago, I had some moss growing between my grass. Once I limed, the grass grew in better and I haven't seen the moss since.
I think that your best plan would be to lime it up to a ph of 6.5-6.8 and then just do what you can to get the grass to grow thicker.
Why do you add sand to your lawn? The structure of your soil will dictate how much lime you are going to have to apply. For example, the dirt in my front and back yards are different enough that I need to apply double the amount of lime in the back to get the same effect. This has something to do with the soil weight and the front being more sandy.
I also believe that Paul generally discourages aerating as he sees it a waste of time.