There are many different species of moss and they are usually picky about pH, but there are ones that like acid soil and ones that like alkaline soil and everything in between. Weeding may help because mosses don't handle competition from vascular plants well at all. They are often found on nutrient poor soils because they can handle those conditions better than a lot of other plants. The challenge will be getting them to grow on potting soil without being overtaken by weeds.

Most mosses prefer shallow soils. I do not think that Miracle Gro potting soil is very good for moss growth unless you are watering heavy every day. You may want to try the felt layer method. The method was developed by
Richard R. Smith and is similar to the Japanese use of materials in their roof gardens. He has a handbook that is roughly $20. The link is to his site. While I only know Rick by emails I do not receive any financial benefit by recommending his site. It is the information and images that speak well of what he has done. Check it out.

Here is a link that might be useful: New Moss Gardening

Thanks. Great leads. I'll leave some of the miraclegro just for filler and top with a few inches of soil from the property which (you're right, lycopus) isn't particularly rich. That should take care of the soil matching. Barbara Damrosch recommends burying a few sheets of newspaper for weed control so I'll do that over the miraclegro before topping with the new soil. I ordered the pamphlet. I'm curious about the felt method. Thanks for that lead too terrestrial_man. Putting in that forsythia opened the door for clover, grass and tree seedlings - it was growing around all of those cuttings. I hope I can undo the damage. I saw a salamander on the mossy side of the house over the weekend. I'll do a lot for a salamander.

I saw Terrestrial man's August 2 post and it renewed my interest in mosses. I ordered Rick Smiths booklet and was delighted with his information and enthusiastic writing. Lots of information here!

After receiving the book, I went out in the backyard and found some nice Thuidium delicatulum. This keying out of mosses is..... shall we say, challenging. Here is a nice Fern moss picture (Thuidium) growing on a RR tie.

OOps, sorry about the absent picture. Here is the Thuidium.

That doesn't look like Thuidium. Don't recognize the species though.

Thanks, Lycopus. Maybe it is not Thuidium. Can someone here suggest a correct genus? Or steer me in the right direction?