Cinder Block Garden: How to Build a Cinder Block Planter

A cinder block raised garden bed is a garden space that uses cinder blocks as the primary structural material. Like other raised garden bed DIY projects that utilize recycled materials, such as pallet wood, the cinder blocks hold new garden soil in place. A cinder block planter is resilient against sun and water damage, and it provides your plants with exceptional drainage to prevent root rot, pests, and fungal diseases. Cinder blocks are a unique material you can use to update an outdoor space. For example, you can build a flower garden around your favorite tree or outdoor furniture to create a focal centerpiece in your backyard.

Review these important aspects of working with cinder blocks before you build a garden with this material:

1. 1. Confirm your block material. Some people confuse cinder blocks with concrete blocks or cement blocks since the materials have a similar appearance and texture. However, they differ significantly in weight. If you purchased durable and heavy blocks at a home improvement store within the last year, there is a high probability these blocks are concrete or cement. The material you choose determines the ease of working with the product.
2. 2. Consider the origins of the cinder blocks. The building material can pose a few health concerns. Production of cinderblocks has decreased in the last fifty years; therefore, many cinderblocks in circulation are recycled or reclaimed items. To create these lightweight blocks, manufacturers used Portland cement and a byproduct from coal plants known as fly ash. This substance can contaminate local soil with heavy metals and carcinogenic chemicals. Further issues can occur if your cinder blocks originally came from a factory or site where they retained residue or radiation from manufacturing processes. Placing such blocks in your yard or garden could contaminate the surrounding area. Natural runoff and leaching would likely carry these harmful substances into local waterways and damage nearby ecosystems.
3. 3. Find safe uses for cinder blocks. Considering the associated health risks of using cinder blocks, you want to avoid planting a vegetable garden in a cinder block vertical garden. Instead, build a concrete block garden for nonedible plants. Additionally, use your remaining cinder blocks for other DIY projects, such as a cinder block bench, a cinder block fire pit, or a cinder block wall to delineate your landscaping. Sideways cinder blocks also make excellent container gardening alternatives or accents for an industrial home décor motif. Use cinder block planters to add beauty and color to a front porch, outdoor kitchen, barbecue area, or other small spaces. Or use them as containers for succulents or a miniature flower bed to attract local bees and pollinators.

Follow this simple step-by-step tutorial to build an easy DIY cinder block garden:

1. 1. Measure your garden area. Confirm your bed design will fit in the allocated location in your yard. Calculating the perimeter and area in a rough stencil or sketch will also help you to budget material costs and forecast your labor time. Double-check your math before you purchase your materials to avoid a second supply run.
   
2. 2. Remove grass or prepare the topsoil. Prepare your location before you begin placing cinder blocks. Begin to remove grass for a garden, or layer newspaper or black plastic across your garden outline to deter weeds from sprouting.
   
3. 3. Lay the blocks with the holes facing up. Each common cinder block forms two connected, hollow cubes. You can place these blocks so the hollow opening faces vertically. This vertical orientation will create a more aesthetically pleasing facade around the outside and increase the stability of your cinder block wall.
4. 4. Secure the blocks in place. Fill the vertical holes of the cinder blocks with soil or drive a wood stake or a piece of rebar in the corners of your wall to secure the next level of blocks. An added bonus of filling your cinder blocks with soil is you create small, individual gardens. Use these to plant herbs or an invasive species that might not coexist well with neighboring plants.
5. 5. Fill your DIY garden with drainage material and soil. Place gravel, pebbles, or charcoal on the bottom layer of your garden. This increases the drainage of excess water and improves airflow to your garden soil. These factors deter weeds and ward off plant diseases and pests that thrive in moisture-rich soil environments. Then add a thin layer of mulch, which will break down and replenish your topsoil. Finally, use a wheelbarrow and shovel to fill your DIY cinder block raised garden bed with native soil, potting mix, or the best soil you have available to meet your plant requirements.
   

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