Build Your Own Square Foot Garden
It’s that time of year again – the first pitch has been thrown out and the pale people of winter have started to emerge in search of a few rays of vitamin D. Around this time, we also start seeing the mailers that advertise the sales at the local nurseries. Just like their yearly ritual of making New Years resolutions, the people of winter resolve to cast off their ‘brown thumb’ stigma and make a go of growing some of their food at home. Annie and I happily accept this challenge and have a decent track record of keeping things alive until fall. Typically, we grow our herbs, veggies, and flowers in pots using your run of the mill potting soil from Home Depot. This year, we decided to take a crack at the square foot garden method and see what happens. Off we went to the Google machine to get a few ideas and plans.
After some research, we settled on an elevated garden that would be about waist high and could sit on our concrete patio (where we get the best sun). The planter box would sit on legs and have room underneath for flowers or to store the garden hose. The dimensions are 4 feet by 2 feet, and we would mix our own soil based on the recipe we found on The Square Foot Garden (Mel’s Mix).
Materials (all from Home Depot)
– Wood (legs): 4×4 (4 of them at 36″ each)
– Wood (sides): 2×6 (4 of them at 48″ and 4 of them at 24″)
– Wood (bottom of box): 2×4 (2 of them at 37.5″ and 4 of them at 45″)
– Box of 3″ screws
– 2 hooks w/ screws
– 2mil plastic drop cloth
– Weedblock landscape fabric
– Stapler w/ 3/8″ staples
– Soil : Perlite (1 bag)
– Soil: Compost (2-3 bags of different kinds)
– Soil : Peat Moss (1 2lb bag)
– Chop saw (miter saw)
– Pocket hole jig
– Utility Knife
First things first – make some little boards out of big boards. I used my miter saw to make these cuts and measured twice before cutting. The more things I’ve built, the more I’ve learned the importance of getting really accurate cuts that are square. Seems obvious, but not paying a lot of attention to this makes for a miserable fitting and sanding process. It is also worth noting that when you get wood cut at the lumber yard, they typically only make rough cuts and often times they aren’t as accurate as you’d like. I also like to cut off the raw end of any new boards I get before measuring for my cuts. It gets me a crisp edge that is square.
The only boards I didn’t cut to size were the bottom 2x4s. I wasn’t sure how long I needed them or the configuration I wanted, so I waited until the frame was assembled before measuring them for cuts.
Then I started building the two boxes that would form the sides of the square foot garden. Simple enough – Just dry fit on the ground, pre drill holes, add some wood glue, and drive some 3″ screws. I then took the two completed boxes and stacked them on top of each other. I planned to then set the legs into the corners and use a carpenter’s square to make sure it was plumb and level.
I attached the legs with the garden upside down (legs shooting up and boxes on the ground). I then flipped it over to see how everything sat on level ground. No issues. I think this also has a lot to do with making sure all my cuts are exact. I left the 4×4’s level with the top of the garden to provide a place to place a bowl or something when harvesting veggies. I contemplated recessing them and covering them with soil for a cleaner look, but decided the convenience was a worthy tradeoff.
While I was deciding on a configuration for the bottom, I moved the garden into its final resting place (the backyard). Next I installed the plastic lining around the inside of the garden box. My thought was that this would prolong the life of the wood and might help retain moisture over longer periods of time. I doubled up the liner and then trimmed it to be flush with the bottom of the garden box.
For the base, I decided to use 2x4s to serve as slats along the bottom with gaps designed to let the water drain out of the box. I was originally looking at a sloped plywood design but thought this was a better solution. Instead of screwing them in from the outside of the box and having even more screws showing, I used my pocket hole jig to allow for them to be installed from the inside of the box. Screwing in the slats was kind of awkward as I had to hold them in place while screwing them in. I probably should have cut them a bit longer for more of a friction fit, but after I got them in, it seemed pretty strong.
The final step of frame construction was to add some landscape fabric over the slats. This was primarily used to hold in the soil and easily allow the flow of water through the slats. I wrapped it under the slats and secured it with staples. I then worked my way around, cutting and trimming until the bottom was covered. Throw on a couple hooks for shovels or gloves (we painted them red), and you’re done.
Success! Now we need some soil and plants.
We chose a well respected (that sounds weird) recipe for the soil in our square foot garden. It is based on a recipe we found online called Mel’s Mix.
– 1/3 Perlite
– 1/3 Compost (mix equal amounts of a few kinds)
– 1/3 Peat Moss
We mixed ours in small batches using a Home Depot five gallon bucket (one bucket of each, then mix together). You can find formulas online that can help you calculate the cubic feet of soil you need and then you can break it down into the components.
Boom! Now we have a square foot garden.
We planted some shishito peppers, red peppers, yellow peppers, cilantro, basil, and arugula to test our new garden.
Here is the final product. Let us know what you think in the comments.