Building A Simple Cedar Raised Bed

As mentioned in my Small Gardens Can Make a Big Difference post, I completely changed directions with my garden this year. I built my first raised bed not thinking we’d actually get it set up in time for this year’s garden, but we did.

Buy a Raised Bed Kit or Build it Yourself?

There are all kinds of raised bed kits and fancy corner braces you can buy. I am going to share with you how I built my simple 4 ft. x 8 ft. cedar raised bed.

I decided to use cedar because it is naturally rot-resistant, and I hope it will last a little longer than pine. I also did not want treated lumber because I have concerns about growing food in treated lumber. While I have read that treated lumber can be safely used these days, I opted for untreated cedar deck boards. You can build a raised bed more cheaply with cedar fence pickets, but the cedar deck boards are a thicker piece of wood – again, I am hoping it will last a little longer.

Tools Needed

• Saw – I used our compound miter saw
• Drill
• Speed square , optional, but handy
• Tape measure

Raised Bed Materials

• 6 – 5/4 in. x 6 in. x 8 ft. untreated cedar deck boards
• 2 – 2 in. x 2 in. x 48 in. cedar deck balusters
• 2 in. outdoor deck/construction screws

Instructions for Building a Raised Bed

Cut each 2 in. x 2 in. x 48 in. baluster board into four 1 ft. lengths.

Lay two of the 8 ft. cedar boards side-by-side with the ends flush. You can do this on the ground, but my knees do not appreciate kneeling on the ground. Luckily, we had some sawhorses with some 4 ft. x 8 ft. sheets of OSB decking sitting on them in our barn – they made a fine worktable.

Place one of the 2x2x1 ft. cedar boards you cut at each end of the 8 ft. side-by-side boards. These first two will be the corner braces. Once this section is standing up, the raised bed will be a double layer, 1 ft. tall bed.

I put the 2x2s underneath my 8 ft. boards so that I could drill pilot holes through the deck boards and into the 2 x 2s. One drawback of cedar is that is can split easily, so I recommend pre-drilling the holes for the screws.

I found it handy to use my speed square to first make sure the ends of the boards were lined up square and flush and then use it as a guide for the pilot holes so that they are lined up. Not required, but it makes the finished product look nice and neat.

Using outdoor/deck screws (we personally love GRK construction screws), attach the two 8 ft. boards to the two 2×2 corner braces.

Taking two more 2x2s, place them roughly dividing the 8 ft. length into thirds. This gives you a total of four supports joining the two 8 ft. length boards together. Pre-drill the holes and screw the 8 ft. boards to the 2×2 braces. 

Note about the picture below: the 2×2 braces are shown on top of the boards to show the placement of the braces. Attach them with the 8 ft. boards on top of the 2×2 boards so that you are screwing the 8 ft. boards to the 2x2s

Now repeat the whole process with two more 8 ft. boards to build the other long side of the bed.

Cut the two remaining 8 ft. boards in half.

Note: I measured my two remaining 8 ft. boards. Yes, they are supposed to be 8 feet long. But I discovered mine were a fraction of an inch longer. Better long than short, I guess. ? Both of my remaining 8 ft. boards were the same length, so I cut them in half, which was just a fraction longer than 4 ft. If I had measured and cut them at four feet, two of the boards would have been longer than the other two. I wanted my short end boards all the same length.

Take one of the 8 ft. sections and stand it up with the 2×2 braces on the inside. Place a 4 ft. board at a 90-degree angle to the long section. Using a clamp to hold the boards together, drill pilot holes through the deck board and into the 2×2 corner brace and then screw them together. Stand up the other 8 ft. section and repeat this process at the other end of the 4 ft. board. Now do it again and add the second “layer” 4 ft. board.

Where the ends of the short boards meet the ends of the long boards, I drilled more pilot holes and added more screws. Probably not necessary, but just gives it a little more strength.

Repeat the process with the remaining two 4 ft. boards on the other end and you are ready to go!

Setting up the Raised Bed

We put a layer of weed barrier down and set the raised bed on top of it. I have read about folks putting a layer of cardboard down too. It will break down under the soil but in the meantime will also help kill the grass if you are setting your raised bed on top of a grassy area.

Ready to Fill and Plant

Now all you need to do is fill it with soil. HA. That can be a little overwhelming too. There is a lot of advice on the web about creating your own soil. You can also buy a load from a landscape business. But make sure you trust the company and know the quality of the soil you are getting. It is not the cheap way to do it, but pressed for time we bought large bags of container soil, some garden soil, and bricks of peat moss and mixed them all together. Next year we will also work some compost into the soil.

Learn how to make compost from start to finish.

According to my hubby (who has 10 green fingers and 10 green toes, not just a green thumb), when you are planting in a raised bed, it is basically a large container, so you do not want your soil mix to be too “heavy.”

Mulch is Your Friend

Once we had everything planted, we added some wood chip mulch around all the plants to help retain moisture (the picture above was taken before we mulched). Containers and raised beds will dry out more quickly than in-ground gardens. It’s a good idea for in-ground gardens too. So mulch, mulch, mulch.

Ready to Build Another One

Our raised bed has worked out so well this year, I bought all the materials to build another one. I am really looking forward to another day of being unsupervised with the power tools. ?

Building a raised bed is not difficult and does not require a lot of expensive equipment or woodworking experience. You would be surprised how much food or herbs you can grow in a 4 ft. x 8 ft. bed. Being even one foot off the ground is easier to work on and the 4 ft. width makes it easy to reach everything. Next year I plan to set up soaker hoses or a drip line for effortless watering, but the 4 ft. x 8 ft. size is easy to water even when you are watering by hand.

Remember, “when you garden you grow” and “playing in the soil is good for the soul.” Now go grow something! You’ll be so glad you did.