Raised Garden Beds Made From Concrete Blocks: How To Make A Cinder Block Garden

Cinder Block Garden Bed Full Of Fruits And Vegetables

(Image credit: Willowpix)

last updated 5 May 2021

Are you planning on making a raised bed? There are a lot of options when it comes to the material used to build a raised bed border. Wood is a common choice. Bricks and stones are good options, too. But if you want something cheap and attractive that’s not going to go anywhere, you can’t do better than cinder blocks.

Keep reading to learn more about raised garden beds made from concrete blocks.

How to Make a Cinder Block Garden

Using cinder blocks for garden beds is especially nice because you can so easily pick your height. Do you want a bed close to the ground? Just do one layer. Want your plants higher and easier to reach? Go for two or three layers. If you use more than one layer, make sure to place it so that the joints between the blocks in the second layer sit over the middle of the blocks in the first layer, just like in a brick wall. This will make the bed much sturdier and less likely to fall.

Stack the blocks so the holes are facing up too. This way you can fill the holes with soil and expand your growing space.

To make the bed even stronger, push a length of rebar down through the holes on each corner. Using a sledgehammer, pound the rebar down into the ground until the top is level with the top of the cinderblocks. This should keep the bed from sliding around. One in each corner should be enough when using cinder blocks for garden beds, but you can always add more if you’re worried.

Dangers of Cinder Block Gardening

If you search online for cinder block gardening ideas, about half of the results are going to be warnings that you’ll contaminate your vegetables and poison yourself. Is there any truth in this? Just a little. The confusion stems from the name. Once upon a time cinder blocks were made of a material called “fly ash,” a byproduct of burning coal that can be harmful to your health. Cinder blocks haven’t been mass produced with fly ash in the U.S. for 50 years, though.

The cinder blocks that you buy in the store today are actually concrete blocks and totally safe. Unless you’re using antique cinder blocks, there should be no reason to worry, especially when cinder block gardening for vegetables.

The only child of a horticulturist and an English teacher, Liz Baessler was destined to become a gardening editor. She has been with Gardening Know how since 2015, and a Senior Editor since 2020. She holds a BA in English from Brandeis University and an MA in English from the University of Geneva, Switzerland. After years of gardening in containers and community garden plots, she finally has a backyard of her own, which she is systematically filling with vegetables and flowers.