Raised garden beds are one of the best things you can do in your to make your garden more productive. A raised bed will warm up quicker in the spring, compact less quickly, drain faster than ordinary soil and is typically filled with high quality soil. Our raised beds started as native soil (clay, and rocks) but over the years with the addition of amendments, have evolved into a rich loam.
WHY a BRICK Garden Bed?
The biggest problem I have had with raised bed in the past is that wood will typically rot. The high humidity and warmer climate in the Southeast are a challenge for any wood. Even landscape timbers (which you DO NOT want to use for garden vegetables) will rot after a few years. Last year we tried an experiment, which consisted of using discarded pallets (Oak) to create raised garden beds. They actually worked pretty well. But they rotted. So earlier this year I bought the materials to replace a section of low retaining wall and replace the “pallet” beds with something more durable. Below is a picture of a pressure treated landscape timber that came off of the old border. It’s only five years old and has rotted pretty badly.
Home Depot recently repriced some of their 4×8 landscaping bricks (technically pave stones, but they look, feel and taste like a brick, so I’ll call them a brick). They are now priced at 40 cents each, which makes a raised bed project reasonable. Building a garden bed with these “bricks” is still somewhat expensive compared to wood, but your raised bed will last forever, or at least until the next owner tears it down. At this price, a 4×4 bed will cost you $36 in bricks, $10.00 in construction glue, and about $5.00 for a bag of paver base for a bed with 3 courses of bricks, that sits 6 inches high. Your total would be $51.
You’re not going to save money by building a garden bed with with brick. You will however get durability and in my opinion, a more aesthetically pleasing garden than by using wood.
My beds cost a bit more to install than this. Mostly because I also replaced a rotting wood border with the bricks as well. I ended up using a total of 240 bricks. I replaced a 24 foot wood border and attached two 4.5′t by 3.5′ beds to them.
I also had to use more bricks than you normally would because my property is sloped, I mean it’s really sloped. There isn’t a flat piece of land on my entire property. The border is part of a water stop for a french drain I installed a few years ago to help keep the uphill part of my land from moving to the other side of my property.
I really wanted to add a total of four beds but I ran out of bricks. Normally I would have gone out and bought more but considering my current job situation, the rest will have to wait. With apologies in advance to any brick masons who may be reading this, here is a step by step instructions on putting in a raised garden bed made of brick.
Tools You Will Need
Bubble Level - A small six inch one will do, I have several that I used, a 6 inch, a 24 inch and a 48 inch. The different sizes come in handy depending on whether your trying to level a single brick or a series of bricks.
Straight Edge - My 48 inch level is also a straight edge, but if you don’t have a long straight edge a 2×4 that isnt warped will do the trick
4 pound Mallet - This will come in handy when your leveling out your base course of bricks. placing piece of two by four over the bricks and lightly tapping with your hammer will help get them adjusted so that they are level. If an individual brick is giving my trouble, I’ll use the bottom of the wood handle to “tap” the brick into submission. If you don’t have a mallet then a regular hammer will do as well
Wide tipped cold chisel - If you’re really good at planning your layout, you won’t have to cut any brick. If you’re like me you’ll need a cold chisel to score a line in the brick and tap along the line to break it to the size you need.
Masons Twine - You’ll need this to mark out the layout of the planter. regular string will do as well. We usually keep some masons twine around as it’s handy and relatively inexpensive.
Landscaping Spikes or Stakes - You’ll need this to mark the outline of the garden bed. I keep a bunch of 12 inch landscaping spikes around as they come in handy for a number of different yard projects.
Hand Trowel - A regular garden trowel will do. If your digging a small foundation for these bricks you don’t want to dig a very wide trough for the first course. Eight inches should be sufficient.
Tools That will Help
A string level - If your absolutely fanatical about having a perfectly plumb course of bricks then you can set up a masons string with a string level to use as a guide.
T Square - I have a large four foot one that is one of my best friends. It has been involved in almost every project I’ve taken on.
Getting most of these tools are easy, getting them inexpensively can be more of a challenge.. My favorite tools store, especially for these types of tools, is Harbor Freight Tools, Their prices are great and you can usually find an online code for free shipping!
Diagrams and Pictures for a Raised Garden Bed
I’ve included a number of diagrams and pictures for your raised garden bed project. You can click on any picture in this post and it will open up a new window with a larger version of the picture or diagram you need to look at.
Get Started on Your Raised Garden Bed
The first thing you want to do is layout the square for your raised bed. Use the dimensions of the bricks as a guide to figure out what the exact size of the square or rectangle will be. Temporarily mark the inside corners of the square with a spike or smalls stone. Hint: There’s an old trick to help you set a perfect square. If you measure diagonally from corner to corner on opposing sides, a perfect square will have the same dimensions. A diagram is worth a thousand words!
You’ll want to set two spikes on the outside of each corner. The spikes should line up with where the inside of the retaining wall will be. You’ll tie the masons twine to two of the spikes that line up with the inside of the retaining wall. You’ll want to do this for all four sides. (More apologies to brick masons, they would normally use the outside of the wall and also “plumb” the line).There’s a diagram to the right to help you visualize this.
Once you have your string set up into a perfect square you’ll need to dig a trough. The trough should be approximately three inches deep. 1.5 to 2 inches for the paver base and one inch for the first course of bricks. You don’t want the trough to be too wide. One inch of either side of the brick would be ideal. So it should be 8 inches wide.
If you’ve finished digging out the trough. you’ll need to set down a layer of paver base. I usually prefer to make my own by mixing one part portland cement to three parts of sand. For a small scale project you’ll probably be better off buying a bag of the ready mixed paver base. First, tamp down the soil in the trough. I use the flat end of the engineer hammer to do that. You ‘ll also want to tamp down the paver base once you set the bricks down. If you don’t tamp down the soil and the base you run the risk of it settling down after a rainfall and undermining your garden bed walls.
I usually put down enough base for three bricks. I’ll then lay the bricks down and level each one, front to back and side to side. You can also use a section of 2×4 to level a few bricks at a time. Lay the 2×4 over the bricks and with your engineers mallet. Lightly tap the area that is too high. Go easy! You can over-correct with one tap that is slightly too hard and have to start over again! Here’s a pattern that I recommend you use if your making a square raised garden bed. This pattern will make it easy to overlap the second layer of bricks over the first.
User your bubble level to check the level of each brick, front to front and side to side. See Pictures below:
It is critically important that the first row or “course of bricks is plumb! If they are not, the entire raised garden bed will be off kilter!
Once you have your first row set and everything is square and level you can start your second row. You want the bricks in the second row to overlap the first
row. When you glue them in, having them overlap will reinforce then entire garden bed. I’ve included yet another diagram showing how the second course should overlap the first course of bricks. I use Loctite “500″ landscaping glue. It sets up with a very strong bond. You can of course use mortar, I prefer not too for a raised bed. It complicates the project and it also takes away the benefit of good aeration and drainage through the wall. When Gluing the bricks, I put a glob on either end of the brick and set it in place. As an alternative, you can set globs of glue on the underlying row and place the bricks on top of them. When you set the bricks down, press down firmly so that the glue spreads out over a good contact area. The glue is also a very nice lubricant when you set the brick in place. If the first course is not level the brick will slide away. You have to keep a close eye on freshly glued bricks as they will tend to slide out of place.
Above is a picture of a corner showing properly laid bricks that are overlapping The Corners are especially important, the overlap on the corners will add structural strength and stability to the overall raised garden bed. Give the second row of bricks at least one half hour to set before adding another course of bricks. Adding another course of bricks before the glue sets risks moving the bricks underneath. You can continue adding rows of bricks until you’re satisfied with the height of the raised garden bed. I would suggest a minimum of three rows. When you have laid and glued the final row of bricks, let them set for at least twenty four hours before adding soil to the your new raised garden bed.
Here’s a picture of the finished garden beds. You’ll see that the bed on the left has a corner that is not level. That corner has a huge boulder underneath, so I went with a slightly uneven bed there. I will also be attaching a border to it sometime later. There’s no glue and just a sand base on that corner.
I hope you’ve enjoyed this post. Better yet, I hope it’s inspired you to put in a raised bed before you get your garden planted! Let me know what you think. I’m especially interested to see if you enjoy this type of post and whether you’d like to see more of them.