Grit Blogs > Of Mice and Mountain Men

Square Foot Garden Project: Step 1

A photo of Allan DouglasLast year when I put the garden to bed for the winter I pulled out all the nightshades for burning, then tilled everything else under and covered the dirt with a blanket of the fall leaves and grass clippings.  Over the winter we added kitchen scraps and ash from the fireplace.  There was nothing scientific about this, just toss it all in there somewhere.

Changes in the Offing

I was going to need to make major changes to my little garden plot this year; there is too much slope and heavy rains wash away my top soil and re-arrange my crops.  They don’t like being shuffled about and some of them decided they’d rather just die than live an integrated life style.

My first thought was to build several retaining walls of landscape timbers and terrace the garden to level out the growing areas.  Even at the beginning this did not seem like a perfect solution: Some of the retaining walls could get to be around 3 feet tall.  Those would require tie-backs to keep the dirt from pushing the walls over.  If I curved the walls, it would help but making curved walls from straight timbers is a bit problematic itself.  Digging (or drilling) pits for concrete anchors and burying steel tie-rods between anchors and walls is a fair bit of work, and the rods will interfere with tilling.  Then there is the issue of water retention.  Someone who knows this stuff warned me against this plan because water would just drain out the bottom by the terrace walls.

So I began looking for a better solution.  I came across several mentions of Mel Bartholomew’s Square Foot Gardening method, and it seemed like a good alternative.  This system has been around since 1981 and still has many devotees.  This method uses raised boxes filled with a special “dirt” mixture and a grid-work planting lay-out instead of planting in rows.  I decided to give it a whirl.

Building the Boxes

 A couple of weeks ago I borrowed a monster 8 hp rear-tine tiller and worked the garden again.  I won’t use that soil right away, but it will come in handy later.

Then we went to Lowe’s and bought the lumber and deck screws.  I’m going to start with six 4’x4’ boxes, so I bought twelve 8 foot 2x6’s; untreated, and a box of 2½” deck screws.  Total cost $96.00.  I knew I would need 72 screws, but the boxes only give a weight, not the count of screws contained.  They had one pound boxes and 5 pound boxes.  I decided to play it safe and buy the 5 pound box.  I could have used cheaper screws - this box set me back $30, but I was afraid cheaper, interior use screws would rust out and the boxes would fall apart.

Marking board ends 

I started by cutting all the 2x6’s in half and marking a line 1½” in from one end of each.  This helps me center the screws in the adjoining 2x6.

Drilling shank holes 

Then I drill three shank holes for the screws in just that end of each board.  I used a drill press because I have one handy - and because it insures that the holes are straight and square to the board, but a hand drill would work too.

Assembling the Ls 


I found a spot where I could stand one 4 foot board upright and lay another on a work counter and get the corners to come together properly.  I could have laid them on the floor, by my old knees complain bitterly when I do a lot of up-and-down, up-and-down stuff, so I prefer to work in a standing position.

I used a QuickClamp to hold the edges of the boards even, and the soft rubber faces helped keep the boards from shifting in and out while I drove the screws with a power screwdriver/drill.  I used a small framing square to get it close to square, but wasn’t going to get to obsessive about that.  This is not furniture after all.

Making the box 

I built each box in two steps, by first making two ‘L’ shaped sub-assemblies, then flipped one over and set it atop the other and drove in the screws.  This seemed to work better than trying to attach each side one at a time and having to roll the assembly around… especially at the point where it would be ‘U’ shaped and the chances of cracking one of those loose legs is pretty high.

Marking for grids 

While I have easy access, I take the chance to mark the top edges of the box for the grid work that will divide up the planting box.  I will probably just use string as a means of visually dividing up the box for planting, some use wooden slats.  This grid will yield 16 cells per box, each almost 1 foot square - it actually works out to 11 3/4” if you divide up the interior dimension equally.  I taped the yardstick in place for the photo as I am working alone, to do the marking I just held it in place against the left vertical and marked the rail at each point.

Three boxes done three to go 

As I get them done, I carry the boxes out and set them on my loading dock and out of my way.  Three done, three to go.

Box of screws 

As it turned out, when all six boxes were done, I had more than half of the box of screws left.  Two one pound boxes probably would have been sufficient for 6 boxes.  Oh, well, I’ll probably be building more, I’ll use these up eventually.

Boxes dug in 

Then I spent about 3 hours scraping the composted, rich top soil back out of the area where I want to mount the boxes, and digging three of them in so they are level.

Good Dirt; Good Start

Our soil here is fractal red clay.  Red clay has two states of being: if it has rained recently it’s mucky and sticky; if not, it’s hard as concrete.  Neither state is ideal.  Being spring, it has rained - a lot - recently, so the clay under the garden soil was pretty sticky; gumming up my tools and my shoes, but at least I didn’t need a jackhammer!

The composted soil that I removed was nice, black, rich-looking soil and was just infested with earthworms.  It was very gratifying to see that my efforts to amend the red clay last year produced such good results.  I will use this composted soil in the Mel’s Mix that will go back into these boxes once I have them all in place.

This is all I can do for today, I’ll move more top soil and dig in the other three boxes during the evenings next week. 

In my next installment we’ll make up the Mel’s Mix and fill the boxes.  It should be safe to plant outdoors next week and I’ll transplant the seedlings that have already sprouted in an indoor mini-greenhouse.

Thanks for reading!