Introduction: Golden Ratio Plant Pot

For this Plant Pot, you will need:

  • 1 High Impact Polystyrene Sheet (30x20cm)
  • 1 Ruler
  • 1 Pigment Pen
  • 1 Protractor
  • Tape
  • 1 PVC Pipe (4cm Diameter)
  • Plaster Powder
  • Water
  • Scissors/knife
  • a Drill

Make sure you wear an apron when working with plaster, and be careful when handling it in clean environments. It can get very messy!

Step 1: Drawing the Mold Net

For the Net of the mold, you will need to trace a regular pentagon with 4cm side lengths with your pigment pen. The interior angles should be exactly 108˚ on all 5 sides.

Then, draw 10 identical isosceles triangles with a base of 4cm, side lengths of 6.5cm, and interior angles of 72˚, 72˚, and 36˚. It should turn out as a golden triangle.

make sure to draw the net on the Non-lustrous side - this side will face out on your finished mold.

Step 2: Cutting the Net

Use a sharp and hefty pair of scissors to cut through the thick High Impact Polystyrene, following the lines you drew for the net earlier. Cut every line all the way through as this material does not fold very well during the assembly process. When every component is cut out, peel the protective film off the lustrous side to prepare a smooth and shiny surface for the next step.

Step 3: Assembling the Mold

Fold the net as shown in the photos, making sure to completely seal every gap between the pieces.

Face the lustrous side in for a smooth final product.

Only tape the mold externally to avoid tape marks on the final product.

Wrap the entire mold with tape twice once assembled

Step 4: Building the Core

Use a short PVC pipe and a thicker piece of High Impact Polystyrene for the core. Trace and cut the polystyrene to fit the inside diameter of the PVC pipe, making sure to cut accurately to prevent leaks. Press the end of the pipe down on the polystyrene to fix it in like a cap. If the polystyrene was cut correctly, the tape should not be necessary to prevent leaks or to keep it in place.

Step 5: Mixing and Pouring Plaster

For the plaster mix, add 3 yogurt cup's worth of plaster powder and 2 yogurt cup's worth of water into a bucket and mix thoroughly. Check for clumps. If there are small bubbles and the mixture is too runny, add half a cup of plaster powder to the mix to thicken it.

Fill the mold halfway with the mixture. Push the core 5/6 of the way in, and fill the edges as needed with the remaining mixture. Use tape to secure the core while the plaster dries so it sets in position.

Step 6: Removing the Mold and Core

After at least 1 hour of setting, use scissors or a knife to cut the tape at the edges of the mold. The mold should slip off the plaster with ease. To remove the core, gently wiggle it until it comes out of the plaster.

Drill a drainage hole at the bottom with an appropriately sized drill bit, depending on your preferences and the type of plant you are planting.

Your are now done!