This video shows how to make a sustainable hypertufa container. These troughs are typically molded using a mixture of portland cement, perlite, and peat moss, but in this tutorial, I’ll be working with coconut coir as a more sustainable replacement for the peat moss. I’ll also be using a sand mold method to shape my container. This method allows for much variety and experimentation with shapes, since you aren’t restrained to a box or bowl shape, as in other methods.
To start, you’ll need to break up the compressed coconut coir bricks by rehydrating them with water. It may take more water than you think. You’ll then need to let the coconut dry before mixing the hypertufa.
Sustainable hypertufa recipe
Though a 1:1 ratio is what is recommended for the version of the recipe that uses peat moss, I found that coconut coir doesn’t hold as much water, and so I recommend more of a 1.5:1 ratio of coconut coir and cement to water and perilite.
- N95 mask or equivalent
- Quart container
- 2 quarts of cement
- 2 quarts of perlite
- 3 quarts dry coconut coir
- Water (add a little at a time until the consistency of cookie dough is reached)
Tip: You can adjust this mixture depending on the size of the container you are trying to make.
In this tutorial, I’ll be molding our hypertufa using a sand mold, which gives a more polished finish over the cardboard box or plastic bowl methods.
- First, lay down some plastic on a work surface. You may want to tape the plastic down, too, if you’re working outside. I used a trash bag, and that worked fine, but a thick industrial plastic is recommended, and would be a benefit when unmolding, as the trash bags tend to stretch.
- Next, pour out your sand on the plastic sheet, and wet it so that it sticks together. I wanted an oblong shallow container and so began working on an egg shape.
Tip: Make sure that your sand mold is about the same depth all the way around, and that the bottom is flat. I used a tool to make a crude measurement for the depth of the container and then used a scraper to slice off the top of the sand mound to give it a flat bottom. Remember, we are molding the container essentially upside down, so the top of your sand pile is the bottom of your container. Using a level to ensure the bottom will sit flat isn’t a bad idea, but I only eye-balled it, and it was fine.
- Mold the hypertufa mixture around the sand mold. You’ll want to build the hypertufa up over the container so that you are adding the mixture to the sides of the container first, and the bottom last. Try to add an even amount over the entire surface of the bowl, and pat smooth. You can measure with a thin stick to ensure that the container is about 2 to 3 inches thick.
- Cover the container in plastic for the first stage of curing, and leave where it is for 24 to 36 hours.
- Test the first stage of curing using your fingernail or a screwdriver. When no impression is left on the surface, the planter is ready for the second stage of curing.
- Remove the plastic when the first curing stage is done, and then gently lift the plastic sheet under the container and mold to release the edge of the hypertufa from the work surface.
- Smooth the sides of the planter with a wire brush, and then let it sit in a shady spot for another three weeks of curing.
- After three weeks, you can put the finishing touches on your planters. Hypertufa is naturally porous and will drain water through the material, but if you want it to drain more quickly, drill drainage holes in the bottom of the planter.
- Rinse the planter a few times with water to remove any buildup of lime contained in the portland cement.
Now it’s time to plant your container. Hypertufa are typically used for alpine plants and succulents. See soil recipes here.