DIY Brick Project: Building a Garden Planter

A brick planter adds timeless charm and structural definition to any garden space, creating a permanent landscape feature that will last for decades with minimal maintenance. This weekend project is perfect for DIY enthusiasts with basic masonry skills who want to enhance their outdoor living area.

Before beginning, proper planning is essential. Consider the planter's location carefully, accounting for sunlight requirements of intended plants and how the planter will integrate with existing landscape elements. For this project, we'll create a rectangular planter measuring approximately 1.2m long, 60cm wide, and 60cm high—a versatile size suitable for most garden spaces.

For materials, you'll need approximately 150-170 bricks (allow extra for mistakes), 4-5 bags of premixed mortar, a bag of concrete mix for the foundation, landscape fabric, drainage aggregate, potting soil, and compost. Tool requirements include a brick trowel, pointing trowel, spirit level, tape measure, string line, brick hammer, wheelbarrow for mixing, safety glasses, and gloves.

Begin by marking out the planter footprint using stakes and string, ensuring corners are square by measuring diagonals (they should be equal). Excavate to a depth of approximately 15cm for the concrete foundation. Level the base and compact it firmly.

Pour a 10cm thick concrete foundation, slightly wider than your intended brick walls. Level it carefully and allow it to cure for at least 24 hours before proceeding. This solid foundation is critical for preventing settling and cracking as the planter bears the considerable weight of soil and plants.

Before laying the first course of bricks, plan your bond pattern. A simple stretcher bond works well for garden projects, creating a clean, classic appearance. Snap chalk lines on the foundation to guide brick placement, ensuring straight walls.

Mix mortar according to package instructions to achieve a consistency similar to peanut butter—firm enough to hold its shape but workable. Begin laying the first course by applying a generous bed of mortar along the foundation. Place corner bricks first, then span between them, maintaining consistent 1cm mortar joints. Check regularly with a spirit level to ensure bricks are level both horizontally and vertically, making adjustments while the mortar is still workable.

For subsequent courses, apply mortar to the top of the previous course and to the brick ends before placement. Stagger joints between courses for structural strength, using a brick hammer to create half-bricks where needed for proper bonding. Every few courses, check that corners remain square and walls remain plumb using a spirit level and mason's square.

Incorporate drainage holes in the second course by leaving gaps at intervals of approximately 30cm along the base. These critical openings prevent water logging that could damage plants and compromise the planter structure during freezing temperatures.

Once you've reached the desired height, consider finishing the top course with brick caps or soldier course (bricks stood on end) for an elegant appearance. Allow the entire structure to cure for at least 48 hours before filling.

Prepare the planter interior by lining the bottom with landscape fabric, overlapping edges up the sides. Add a 10cm layer of drainage aggregate, then another layer of landscape fabric to separate aggregate from soil. Fill the remaining space with a mixture of quality potting soil and compost suitable for your intended plants.

After a week of curing, consider applying a breathable brick sealer to the exterior faces if desired. This optional step can enhance durability in harsh climates while preserving the natural brick appearance.

Once planted, the brick planter will develop character over time, potentially acquiring a pleasant patina or light moss growth that adds to its garden charm. With proper construction, this project should provide decades of use with minimal maintenance beyond regular plant care.

For those hesitant about mortar mixing or precision brick laying, consider dry-stacked options using interlocking landscape blocks as an alternative. However, traditional mortared brick offers superior longevity and a timeless aesthetic that complements virtually any garden style.