How to Make a Concrete Planter Using a Mold

Make a planter out of concrete.

Planters are useful to grow plants indoors and within an urban setting. You can make homemade planters out of concrete that iarevery durable, lasting for years even in harsh weather. This planter will be made using two plastic containers as simple molds. You can collect several containers to quickly make a wide variety of planters, allowing you to enjoy variety among your different plants. This project is basic enough to be executed by someone with no previous experience.

Things You'll Need

• Plastic containers
• Petroleum jelly
• Paint brush
• Ready-mix concrete
• Water
• Trowel
• Paper towels
• Drill
• Sandpaper

Instructions

1. Select two plastic containers to use for your mold. One of these should fit within the other, for example, a 16-ounce butter container and a 32-ounce yogurt container. When the smaller is placed into the larger, there should be at least 1 inch of empty space between them.

2. Brush a thin coat of petroleum jelly onto the inside of the larger container and the outside of the smaller one.

3. Combine a batch of ready-mix concrete with water according to the instructions. You can estimate how much you'll need by subtracting the volume of the smaller bucket from the volume of the larger one and adding 10 or 15 percent to allow for a reserve. For example, if the larger container is 32 ounces and the smaller one 16 ounces, mix up at least 18 to 20 ounces of concrete, by volume.

4. Fill the larger container with concrete.

5. Tap the sides of the container with your hand to dislodge any trapped air bubbles, allowing them to rise to the top.

6. Press the smaller container into the larger one until the concrete rises to the top of the larger container. Do not completely submerge it. Some of the concrete will ooze over the sides of the larger container, add this into the smaller one to help keep it in place.

7. Smooth the top of the concrete between the two containers with a trowel.

8. Allow the concrete to harden for 24 hours.

9. Remove the plastic containers from the planter. The petroleum jelly should make this easy.

10. Wipe the excess petroleum jelly off of the planter with a paper towel.

11. Drill a 1/4-inch drainage hole through the bottom of the planter.

12. Sand the planter with 80-grit sandpaper as needed to remove any rough areas.

References

• "The Prop Builder's Molding and Casting Handbook"; Thurston James, 1989