Ananda of A Piece of Rainbow says: These easy to make concrete modular planters are inspired by three of my favorite things: geometric designs, concrete as a creative material, and the tapestry of living walls. Each planter module is created from the shape of an equilateral triangle, the magical geometry which allows a group of modules endless possibilities of forming new shapes and patterns.
The planters are unique, reconfigurable for your space, and allow everyone to create their own mini stackable vertical gardens or large living walls. Follow this step-by-step tutorial with downloadable template to make a few of these, and bring more nature into your home in a modern and stylish way!
What you need
Pourable concrete mix, such as Quikrete 3000lb (used here) or 5000lb.
Box cutter or scissors
Glue and tape for the molds
Plastic containers to mix concrete
Plastic bags for curing concrete
Template for the molds, formatted for 8.5″x 11″ (download template)
Cardboard or thick card stock for making the molds
Project cost: $7 Total time: 1-2 hours to make, 3 days for concrete to cure
1. Print and cut out the template, trace onto cardboard, and cut out the inner and outer molds. The template for the outer mold on page 2 is larger than 8.5″x11″, so rotate it when you trace to complete the shape. Score, fold and tape each mold with scotch tape or masking tape. Fold 3/8″ wide strips of cardboard into triangular shapes and glue them to the inside bottom of the outer molds. These will function as drain holes and openings for hanging later.
2. Screen those really big chunks of aggregates out of the Quikrete 3000lb mix- a plastic nursery pot works great, and leave some small aggregates for strength. Mix the concrete following the proportions recommended on the bag, using the screened concrete as if it is the original mix. Wear dust mask and gloves when working with concrete.
Pour the mix into the outer mold till it’s level with the triangular pieces, then place the inner mold inside, making sure it is centered. Pour the walls using a Popsicle stick to help pushing the mixture down.
3. Let the planters stay in the molds and cure for at least 3 days by misting them daily and wrapping them in plastic bags. This is a very important step to ensure that the concrete hardens as much as possible so they don’t chip or break. The more moisture you can keep in the plastic bag the better.
After day 3, take the planters out of the molds. Since concrete is very alkaline and that can be a set back for plant growth, soak them in a tub of water for a day and let dry. I decided to paint the edges with gold acrylic paint for an added sense of mystery.