Cinder Block vs. Wood Raised Bed – Pros and Cons

Cinder Block vs. Wood Raised Bed

Raised garden beds are becoming increasingly popular. There are several materials you can use to create the walls of the raised bed. In this post, we’ll cover cinder block vs. wood raised bed. 

Both wood and cinder blocks are common for creating raised beds. For those who don’t know, a raised bed is essentially a garden bed raised from the ground and surrounded by walls. These walls are actually what make it a higher bed; otherwise, any bed higher than a ground would be a raised bed. 

There are many advantages to using a raised bed. Generally, it’s easier to work with because of the height. More importantly, if the soil on the ground is not quite healthy, you can use this alternative with good soil. Also, these can help keep rabbits and gophers away from plants. 

Cinder Block vs. Wood Raised Bed: Which is Better?

Oftentimes, which raised bed material you choose also depends on outside factors. For instance, how high you want the bed, what are you trying to grow, and what is the climate like. However, there are advantages and disadvantages to both cinder block and wood raised beds. 

Cinder block Raised Bed Pros and Cons

Pros

Easily Available & Cheap

The number one advantage of cinder block over wood raised beds is that these are easily available. You can find ready cinder blocks for garden beds locally. Also, these are relatively cheaper than wood, so you would not be breaking the bank, putting down some raised beds in your garden. 

Small concrete blocks go as low as just $1 each block. That means you can create raised beds with cinder blocks in as low as $20. For this reason, these are also a good choice for beginners, as these are easy to put together.

Durable

Cinder block is perhaps the toughest material of all the raised bed materials you can use. These can easily give you years and years without needing any fixes or replacement. However, that highly depends on the quality of the cinder block. 

Cheap cinder block can chip or leak, but you can always fix these problems. Since they are so durable, these make a good choice for places that are prone to natural disasters like windstorms and tornadoes. In other words, this material is your best bet against both man-made and natural disasters. 

Good for Stacking

Cinder blocks are also good for stacking. You can stack smaller blocks together to create even higher raised beds. Generally speaking, you want to keep the height of the bed at least 12 inches, but with cinder blocks, you can easily go as high as three feet. 

You don’t necessarily need the same shape and size of the cinder block when stacking them one on another. In fact, you can create a nice design aesthetic by putting a smaller block over a bigger one. If you use a brick pattern when stacking, it can make the whole structure even more durable. 

Flexibility

Cinder block is also quite flexible when it comes to the size and shape of the raised beds. These are particularly good for corner L-shaped raised beds. 

Cons

Heavy to Lift

These blocks are heavy, so working with these requires some tough physical labor. Carrying them from your car to the garden, then placing them where you want to can be a lot of work. Those with a bad back simply cannot work with these heavy cinder blocks. 

These can weigh anywhere from 20 to 40 pounds. Since these are heavy, you might need to hire someone, which would add to the cost of your raised bed. However, you can always ask a friend for help.

Less Heat Dissipation

Another disadvantage of cinderblocks is that they tend to trap heat. This is usually not a problem in the winter, as the atmosphere is already cold. However, in summers, the heat can damage the roots of some plants. 

pH Drop

Some cinder blocks can leach lime into the soil, lowering its pH and making it more acidic. This is not the case all the time and can be prevented easily. If you check the pH of your garden soil regularly, you can monitor if there’s any change in the cinder block raised bed. 

Wood Raised Bed Pros and Cons

Pros

Better Aesthetic

Wood raised beds look the most beautiful of all the materials. They certainly have a better aesthetic than cinder blocks. However, that’s a little subjective, as some people may find cinder blocks to be more aesthetically pleasing. 

DIY/Customized Raised Bed

Wood is a great option for those that are more experienced in gardening, and of course, working with wood. It’s quite customizable, so you can go all out with the shapes and sizes of the garden bed you want to create. 

If you’re taking the DIY approach of making your own wooden walls for the raised beds, you can pretty much cut the wood in the size you want. 

Easy to Install

In contrast to cinder blocks, wood raised beds are quite easy to install. The wood panels are not as heavy to lift and move. However, they do require some tools for installation. 

Cons

Expensive

Depending on the type of wood, your raised bed garden project can set you back quite a lot of money. For instance, cedar, which is the best material for raised garden beds, can be quite expensive. You’re looking at a budget upwards of $100 for a small raised garden. 

Of course, the price varies quite a lot, depending on the wood and where you live. However, in general, wood is more expensive than cinder blocks. 

Untreated Wood Easily Rots

Wood is not as durable as cinder blocks as moisture and water can rot it easily. All wood is susceptible to damage, but untreated wood is all the more vulnerable. Untreated wood is usually cheaper, but it will not last longer than, say, three years. 

They do look more raw and natural but are not the best option if you’re looking for durability. The solution to this problem is going with cedar or redwood. This type of wood is naturally resistant to bugs and moisture. 

Treated Wood Can Contaminate Soil

There has been evidence that treated wood can leak arsenic into the soil. This chemical is not good for your plants, especially if you’re growing vegetables that you’ll be consuming. 

The chemical CCA or chromated copper arsenate was used to treat wood prior to 2003. This was banned eventually for treating wood because of its high content of arsenic. Now, they use alkaline copper quat (ACQ) and copper azole (CA-B) instead.

When buying treated wood for your garden, make sure to do a little digging about what compounds were used for treatment. You can also opt for recycled wood made from wood shavings and plastic resin. However, these tend to be more expensive. 

FAQs

Are Cinder Blocks Safe for Growing Food?

Cinder blocks are generally considered safe for growing food. There has been some concern that these could leak some chemicals into the soil, especially fly ash.

Fly ash was mainly used in cinder blocks back in the day and is not so common anymore. However, there are certain retailers selling cinder blocks with a small amount of fly ash in them. Sometimes these are made from recycled materials from old bricks and blocks. 

The risk is not that high, especially if you ensure there’s no fly ash in them. Another way to ensure no contaminants end up in the soil is to line the block with plastic. 

Is Pressure-Treated Wood Safe for Growing Food?

Pressure-treated wood used to have arsenic, but that has not been the case, since 2003 when the compound containing arsenic was banned for treatment of wood. However, pressure-treated lumber still gets treated with some kind of chemical.

There has not been a lot of research about the compounds currently being used. Therefore, it’s hard to say if these can contaminate soil, and eventually, your food. 

Just to be extra cautious, it’s good to stick to raw natural wood without any treatment. Yes, it will not last as long, but you’ll not have to worry about any chemical contamination of the soil and food you grow. 

Can You Put Pots in Cinder Blocks?

Yes, you can also place pots in cinder blocks instead of putting in soil and planting directly in them. These can provide another layer of protection to the pots. Also, they can help raise their height if you stack them. However, avoid using garden soil for the pots. 

Conclusion

When it comes to cinder block vs. wood raised garden, the bottom line is a personal preference. If you’re putting a raised bed in your garden for the first time, cinder block is perhaps a better choice. Similarly, if you want a more natural look and don’t have budget constraints, wood should be your choice. 

Raised garden beds are great for growing herbs like mint that tend to be invasive. These are also good for growing vegetables, as you use the soil of your choice and manage the plants more easily.