If you are looking for a DIY 4×4 square foot garden plan, this plan is perfect and includes the pictures you need to get it right. The principles applied to build this square foot garden plan can be applied to other dimensions as well, so you can customize the measurements to suit your landscape.
Step 1: Supplies for a Square Foot Garden
- (4) 4 foot long 2×12 untreated rough cedar boards
- (4) 18″ long 4×4 untreated cedar posts
- (16) 6″ carriage bolts 3/8″ thick and 16 matching washers and nuts
Step 2: Tools Needed to Build the Garden
Here are the tools you will need to make quick work of this job.
- electric drill with 1/2″ drill bit
- socket wrench that fits the nuts
- 2 wood clamps
Step 3: Build the Raised Bed Garden Sides
Simply align a post to a side board and clamp them together when they are flush. Then, drill two holes through both to accept the bolts. While still clamped, insert the bolts from the 2×12 side, install the washer and nut on the 4×4 side, and tighten the nut.
Be sure to tighten the nut until the bolt starts to work into the wood but do not over tighten. Once the carriage bolt head is flush with the wood it is not going anywhere.
Repeat the process for the other three sides.
Step 4: Connect the Sides
Now you can assemble your new square foot garden box. To do that, simply do the same thing you did in the prior step, but by connecting the other sides to each 4×4 post. Be careful where you drill since you already have two bolts in that post. Pick a spot an inch above or below the existing bolts.
It is important to note that your 2×12 boards will extend out to the corner where they meet the other 2×12 neatly. Make sure you clamp everything in place before drilling, then drill and install the bolts.
With wood this big and given that this is not fine furniture, you should not have to worry too much about keeping everything square. It will happen naturally, but if you like you can use a square to check it out.
Step 5: Prepare the Location of Your New Garden
Turn the raised garden over and sprinkle some flour along the side to mark the edges. Then, simply dig out the area within this boundary to make a cavity for the garden.
You will notice that you have to dig deeper in the corners to account for the extending posts. This is intentional so that the garden will not move, even if most of the 2×12 boards are above ground level.
Step 6: Install the Raised Bed Garden
To get level just insert the garden and check out the sides using a level. Another good tip is to place a level diagonally across two sides to check them as well. Adjust the dirt as needed until the whole bed is level and you will be done.
Step 7: Add Soil for a Square Foot Garden
All that’s left now is to fill your garden with soil. A good mix for a square foot garden is a combination of peat, vermiculite, and plenty of compost. This makes a rich and light soil that is easy to maintain and holds water without compacting roots.
You can modify these plans as needed to fit your landscape, but keep this in mind. A square foot garden should never be more than 4 feet wide. This is to insure that a person can reach the middle from either side without stepping in the garden. That’s how soil compaction is prevented. So go ahead and build 4×6 or 4×8 beds if you like, but mind the width.
Remember to use untreated wood. The chemicals in treated wood will get into your food and you don’t want that. Natural cedar will last for years untreated, making it a great choice.
By adding a wood bottom to a raised bed it is possible to square foot garden even on a patio or driveway. All that is really needed is at least 6 inches of good soil. This also makes gardening on the deck of a condo or apartment possible.
Have fun building your new square foot garden with our DIY 4×4 square foot garden plan!