millstones in garden

How big are these? What did you use for your mold?

These are approx 26 inches round, 4 inches thick. I used a length of vinyl landscape edging, you can buy this in longer packaged rolls. I fashioned the vinyl into a circle, used a clamp, some duct tape. Also placed into a round plastic pan, the kind you use to place underneath of a water heater, the pans are metal or plastic. The pan keep everything together. This project I used this recipe, a five gallon bucket for measure, one part each, 1 portland cement, 1 perlite or vermiculite, 1 peat moss (sifted or broken up fine as possible). Mix all the dry stuff in a wheel barrel, mix it dry before adding water. As they say "the mixture consistency of oatmeal". I used a piece of 4x4 wood for the center. And within the first day, used a yardstick and screwdriver, scraped the lines onto the top. I had placed several pieces of regular hardware cloth (wire screen) into the project as I went along dumping in the cement mixture. This adds some inside strength. Pat in down, use a piece of 2x4 in your hand, pat to work out the air bubbles. One very important thing is to keep the project covered with some plastic, keep it moist with a water spray bottle, letting it cure very slowly. I let these cure for a month! but the slow curing is how it stays hard, solid and not brittle. These have been out in the garden for 3-4 years, year round, even in the midwest freezing temps. These probably weigh about 50 pounds, so not too hard to lift for moving. I made three of these, and I am ready for a new project soon. These have been so pretty setting in the garden, and most rewarding to make. Thanks for your interest and good luck with your project. Doug

Another question: do you mean peat moss or sphagnum moss? The peat moss I buy is almost a super fine mulch while the sphagnum is pieces and sometimes long tendrils. One of these would make a great fountain. Thanks for the recipe, too.

The package says sphagnum peat moss, I guess it is vacuumed packed, and comes out in hard clumps, but I expect it is the same thing.

Funny, the email dings my I phone, so your question notification came immediately.

Just so happens, I'm at home today working in the garden, cleaning up flower beds. What kind of hypertufa projects have you done before?

Mostly pots for sedum and succulents. I've made a large leaf bowl that I used hardware cloth for additional strength. I'm impressed by the larger projects that you and other folks have made.