Everything we do with the square foot gardens comes right out of the book Square Foot Gardening by Mel Bartholomew. Just go ahead and buy it – you will use it for reference for many years to come.
A standard size for square foot gardens is 4 feet by 4 feet. We chose to use untreated 4 x 6 lumber for this project. We just purchased 2 8-foot sections for each garden, cut them in half and used deck screws to hold them together.
You don’t have to clear the ground beneath it – you can just cut the grass real short – but we did anyway because it needed some leveling. First lay down some ground cloth (keeps the weeds and grass out, but lets the water drain), and then set the square garden box on top.
Next step is to mix the soil. It’s called “Mel’s Mix”. It’s 1/3 course vermiculite (we got it from Logan Trading in Raleigh http://www.logantrd.com/), 1/3 Peat Moss (also from Logan Trading) and 1/3 mixed compost. Compost can be bought from Lowes or Home Depot in bags, but you should really have a good variety. We bought ours from Olde Country Produce & Mulch on Poole Rd. in Knightdale – just got a scoop of it dropped in the back of the truck. Lots of leftover, but found various places around the yard to use it. In the future, we will use our own backyard compost, but that’s another post for the future.
Mix the soil by putting the ingredients on a tarp, then keep folding the tarp back and forth until it’s mixed. Then pull it over next to the garden box and shovel it in.
We highly recommend slats of some sort every 12 inches. That way you can easily see that there are actually 16 distinct squares within the garden, and it’s much easier to keep up with it. You can also plant completely different, unrelated plants in each square.
Now they’re ready to plant. You can either use seeds or pick up flats of your favorite plants from your local garden store. We did a combination of both. We will do a separate post for planting.