Cinder Blocks for Gardening

Cinder Block Gardening Ideas

Cinder blocks have become the next great gardening ideas. I wanted to turn my backyard into a raised cinder block garden. Everything from the web and Pinterest has a plethora of images and ideas on using cinder blocks to create these amazing raised beds. So I wanted my backyard to look pretty and not just another unorganized backyard with vegetables growing.

I did a lot of research and when I finally wanted to use cinder blocks to create my beds I found out that cinder blocks have fly ash and it’s bad for your vegetables or herb garden. It poisonous and it will leach into the vegetables that we will eat.

Using cedar block for ornamental plantings like succulents and other plants you are not going to cook and eat it should be great.

What is Fly Ash

Fly ash is what is left after burning coal basically. Cinder block manufactures still or might use fly ash to reduce CO2 emissions etc. And to meet LEED certification.

There is a strong possibility of poison causing cancer if the fly ash is leached into the root systems of your vegetables or herbs. One thing it will do is cause respiratory distress, kidney disease, and gastrointestinal illness just to mention a few.

Okay so now what? If I can’t use cinder blocks what should I use? The next best thing is to use wood. The best woods to use are the same ones I’ve been using for a while and it works great.

What plastic to use if you are going to use cinder blocks anyway.

There are seven types of plastic you can use but I am only going to talk about the ones that I would use if I am going to make cinder block gardening.

Get some HDPE type 2 that is high-density polyethylene. How would you know if you’re getting the right kind? Ask a person that works at the store to help you out or look for a number type 2 or a triangle with a 2 in it.

My second choice is to use LDPE type 4 that is low-density polyethylene. These two are what I would use. They are a little more expensive but I wouldn’t go cheap if I am going to ingest the things I grow from it.

Wood to use in the Garden

After, many days of debating I think I will stick to wood when using in the garden. I have been using cedar for a while and I will be using cedar fence for the raised bed.

There are teak, redwood, cedar, cypress, and pine. You can use any of these wood to make your garden raised bed. I personally use cedar. Why? Because I am lazy and I don’t want to go searching. Because after you tend the garden all day especially with sweat beating down my face as if it’s the shower before the shower I don’t want to go looking around for woods to get.

When I already know where to get them, Home Depot. Hehehe 🙂 I know there’s the internet and all I do is the research but why when I already know where less stress to deal with.

My reason why I used cedar and it’s not the 2X4 it’s the cedar that is made and cut just for making fences. I used those. I have two cedar raised boxes that are 3feet high because I don’t like to bend so much. They are about two years old and it still holds.

Cedar is lightweight durable and what I love about cedar is that it will stay cool in high-temperature weather like here and it is perfect for my neck of the woods. It naturally bacterial and fungal resistant. It also has natural oil to protect itself from humid climates.

I have not used cypress but I heard that it is comparable to cedar as well. Cypress has a honey color and if you want to maintain that color you have to seal it once a year. However, if you’re using it in the garden you do not want to seal it anyway.

Teak has natural oils to help protect it from the environment plus it is also rot and decay resistance. Hard to find teak in my neck of the woods.

Redwood is great but it will crack and break and if you use them as furniture you must seal it to prevent it from being useful. Using it in the garden you will need to replace them every season.

Pine is usually pressure treated. They are soft with chemicals preservatives so it’s automatically a no-no already. Great for ornamental planting. It only lasts, the max is probably three years. Very susceptible to nicks gouges, and other damages.


Okay so, for now, I am not going to use cinder blocks for gardening because of the fly ash and there’s isn’t much study out there to fully know if it’s totally bad for you. I am going to stick to wood.

The plastic that I would use would be type 2 HDPE and type 4 LDPE that are the safest to use for lining if you are going to use cinder blocks anyway.

I am sticking to wood and I will continue to use the already cut cedar fence wood to build another raised garden bed in my backyard.

Please don’t hesitate to comment or educate me. I love to learn from all. Thanks for coming to my blog I really appreciate it.

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