I make 1 wheelbarrow full of mix each time.
That will make 1 large natural, 1 small natural and a couple of "rocks" to use in the plantings.
I like mine more heavy duty so I use more cement. I have 1 light one and you can scratch it with your fingernail, but it has withstood 2 winters in zone
5 with no problem.
You do need to add a drainage holes. I have a drill I use but you can use a dowel or some kind of plastic pipe. They aren`t really porous but are holey because of where to peatmoss washes out of the cement on the outside surfaces.
All my troughs are at least 6 inched deep. My first and biggest is 16 inches by 24 inches and 10 inches deep. I was too anxious to take it out of it`s mold and my hubby had made a wooden one that I couldn`t take apart and I broke the bottom off of the sides, the sides stayed intact.
I set the bottom down on the raised granite blocks put some hypertufa mix around the perimeter of the base and "glued" the sides back onto the base, It is planted and growing
and holding up just fine.
So if you break one of your troughs don`t throw them out just repair them, it adds character.
Mine are too heavy to hang, they sit on granite blocks.
I make and plant
them in the spring
so I can enjoy them during the summer then sell them in November. The planting look more established and moss has started to grow on them by then too.
$25 to $55 planted. I have seen them at garden shops priced at $45 for an empty one smaller than the one I sell for $25!!
I found the polyfiber at a cement place. Lowe`s has all the other stuff. The temperature has to be at 40 or above for comfort and curing.