If you're not familiar with square-foot gardening, there's a ton of resources on the web. Of course, there's also the original book by Mel Bartholomew (now a classic of gardening literature). But the crux of the system is pretty straightforward:
In a space that's four feet by four feet (16 square feet), you can break up a plot into 16 squares. In each of those one-foot squares you can plant a crop of vegetables. By using clever crop rotation techniques, you can create a garden that yields fresh vegetables all season long. The advantage to this system is that you're never stuck with the traditional row upon row of vegetables that you can't keep up with to consume. You're also never more than two feet away from any space, so tending and weeding become much easier. And you can change the crops to reflect seasonal changes without having to allocate huge plots of land.
There are lots of ways to do square foot gardening, but the preferred method is to use a raised bed. This gives you more direct control over soil quality, saves you having to bend over or kneel in the dirt to do your weeding and planting, and warms the soil faster in the spring. Plus, it gives you the chance to do a PROJECT!!
Of course I have pictures :)
The basic plan I went with consisted of these materials:
4 pieces of 2x2 lumber, 8' long.
4 pieces of 2x4 OSB (chip board) panels, 7/16" thickness.
That's it. Impressive, huh? I'm surprised it worked, considering I wasn't actually following any plans. But that's the advantage to building a square box out of dimensional lumber using simple round numbers like 8', 4' and 2' :)
I decided to build it on my deck so I'd have a relatively level working surface. After moving it into place, my dad said, "Son, next time you build a boat, don't do it in the basement." Sage advice...that sucker was heavy. More on that later.
So here's the basic structure. Start by cutting one of your 2x2's in half. Take one of those halves, and cut it in half again. You now have two pieces 2' long. These will make the front corners of your box. Line up one of the panels flush with the corner of each 2x2 and use 2" wood screws to hold the sucker together. That's your front.
Line up another panel on each side. Make sure you line the panels up with the corner of the 2x2, and not the corner of the front panel...otherwise your dimensions will go a little wonky. What we're looking for is an exact interior dimension of 4' by 4'. Screw those panels in place too (you may need extra hands, or some clamps...I just used a C-clamp).
Next, line up one of your 8' 2x2's with the other end of the panel and screw it into place. Take another 8' piece and do the same with the opposite side. Finally, screw the back panel into place, making sure to line the panel up with the 2x2 and NOT the side panels (yes, this will leave a bit of a gap, but that's OK. It doesn't affect anything).
You should now have a box that has an interior dimension of exactly 4' by 4'. So next, we're going to brace those uprights. You should still have one 4' 2x2 left over, and one 8' 2x2. Because the space between the uprights is less than 4' (it's 4' minus two 2x2's), measure the space between the uprights right at the top of the back panel (this will be most accurate, as the uprights will be bendy at the top). It should be something like 45". Cut your remaining 2x2's to fit. These will make up cross-braces between the uprights. Put one about a foot down from the top (I screwed in from the outside of the uprights into the end of the cross-brace), one about 2' down, and the third another 2' down. You now have a pretty solid box that looks a bit like this:
What you see above was me trying out some branches and misc. scrap trim pieces woven through the cross-pieces, to see if I could make something rustic-looking. I wasn't satisfied with it, so I scrapped that idea and decided a trellis on the front would better serve my cucumber aspirations.
Trellises are ridiculously expensive for what they are. A pressure-treated square trellis can run $25 and up, while a cedar one can run you upwards of $40. The one I installed was hand-made. I hit the decking dept. at Home Depot, and grabbed ten pressure-treated nailing strips (3/4" x 3/4"), at a whopping $0.69 each (total $7.10 after taxes). I then simply nailed three vertically at one-foot intervals, plus two along the outside edges of the uprights, level with the top cross-piece. Then I nailed the other five strips horizontally, starting level with the top cross-piece, at roughly one-foot intervals. Not hard, and far cheaper than the alternative.
By the way, the cedar nailing strips were $1.69 each. Also not expensive, but more than I wanted to cough up for this minimal feature of the job.
Next, I checked for square by measuring corner-to-corner, then corner-to-corner on the opposite side. It wasn't square, but a little nudging got it there. To keep it relatively sturdy, I dropped a 4' piece of old 2x4 inside the box, roughly in the middle at ground level and nailed it in place. What a beast!
I decided I didn't like the idea of an OSB box in my yard. One of the best lessons I got from my dad was this: whatever you do in your back yard, your neighbours have to live with as well; so make it attractive and finished, and they'll appreciate it. In this instance, that means finishing work.
It turns out that 6" pine paneling is expensive. Like, really expensive. So what to do?
Well, 1x6 spruce planks are not so expensive (less than $5.00 a board). I pulled five of those out of the bin so I could get three planks per side (3 times 4' and a bit, times three). Out of each 12' board, I had the cutting dept. at HD slice two pieces 48 3/4". That's four feet, plus 3/4", due to the size of the exterior dimensions of the box. Aha! What I needed was a total of nine pieces that length, which requires five boards. The leftovers (around 46") were actually put to use later, as we'll see.
I started by actually clamping a scrap piece (using an extra block, just in case I needed the good lumber later) to the side panel in order to get the left edge of the plank I wanted to mount on the front. This saved me having to do any measuring at all. Then I lined up my front plank with that board, and along the top of the OSB panel. A couple of pilot holes saved any splitting, and in went some more screws into the 2x2's on either end. From there, I simply lined up each plank right below it.
I decided to butt-joint the side planks. This brought them forward a bit, so they weren't lined up perfectly with the back of the box. What I wanted was to close off the corners at the front though, so that's what I did. Facing the box, you get the end grain of the side planks.
I braced everything by throwing some 1" wood screws through the interior of the box into the back of each plank, just to secure them (without making a bunch of ugly screw holes on the outside).
With the leftover bits of plank, I just invented a closed back panel by screwing the pieces vertically to the lowest cross-brace. This is totally optional of course, but I thought it a good way to prevent vines from escaping down the back.
You'll no doubt notice that there's a big piece of unfinished OSB at the bottom of this thing. That was intentional, as I planned to bury about six to eight inches (it's the latter, since 1x6 is really 1x5 1/2) in the ground. No need to panel that part.
At the back of the yard, I dug up the sod in a 5x5 square, and dug down eight inches. I piled the clay up behind the spot in the old flower bed (you'll see another piece of paneling I used to keep the dirt from falling through the fence into the neighbour's yard). Then, using shear willpower and the might of my unprecedented determination to get this thing in the ground, I managed to get it over the deck rail and onto the lawn so I could drag it into position.
Um...get a friend to help. That's what I learned.
Once in position, I used a couple of bricks and some soil to level it as best I could. Here it is in position:
Due to dicey weather, and having a toddler running around, I actually elected to fill the box before staining it. You could, of course, stain it before you even move it into position. Totally up to you. But first, the fill:
If you do the math (or Google the math, as I did), you'll find out that 4x4x2=32 cubic feet. 32 cubic feet equals 906 litres (since soil products are sold by the litre in Canada, this number is very important). I didn't hit exactly that number, but came close. This was the mix:
First, I put in three bags of 1/4" gravel for drainage.
Next, I put all the soil I had dug out back into the box. My daughter helped.
Next came a potent mixture of 5 bags of black earth compost, 1 cube of peat moss (I couldn't find coconut coir, which I would have preferred...this cube was about 30 litres), 3 bags of garden soil, and 2 bags of cow manure. "Bags" in this case represents a standard 28 or 30 litre bag. I then mixed the daylights out of it. This filled the box about half way.
The next day (because my Camry can only hold so much weight at a time), I went back to the "dirt store" and picked up the same bunch again. 5 bags of compost, 1 cube of peat, 3 bags of soil, and 2 bags of poop. Filled and mixed.
That's a lot of stuff. I'm told I might have to add some sand later on...I'm cool with that. It will depend on what it looks like after this season's crop and the next thaw. Oh...I also added some grass clippings between fills to keep the worms happy; just a tip from an old gardener friend of mine.
So, the only thing left at this point was to stain it. This went on super easy, but if the last thing you stained was a diaper let me give you this advice: stain is not paint. It's less forgiving, and it's really, REALLY runny. Just a heads up. And wear gloves...seriously.
I opted for Minwax Red Oak. It's an interior/exterior wood stain with sealing properties. The only reason for this step was because I like a darker wood tone in general, and I wanted to protect the spruce from the weather. It's not a perfect seal, and yes I know the OSB will break down over time. I also stained the uprights and the trellis, just so it would look pretty uniform. I think it came out not too badly:
The very last stage was to divide the bed into the planting sections. This I did by very cleverly cutting six pieces of old trim that was kicking around the garage into 4' lengths, and creating a grid by laying the pieces a foot apart. I threw in some tomato cages to make sure they'd fit, and that's the whole job.
To plan my planting, I used this handy Kitchen Garden Planner from Gardener's Supply Company, along with Bartholomew's book, which has a ton of useful planting guides for various crops. What's surprising is the amount of food you can grow in something like this. The exact plan I'm using goes like this:
Back row (l-r): 2 cucumbers, 2 morning glories, 2 cucumbers, 2 sweet peas (the flowers are included to attract pollenators).
Second row (l-r): 9 onions, 1 tomato (plum), 1 bell pepper, 2 swiss chard (which you can harvest leaves from practically all season).
Third row (l-r): 2 parsley, 1 tomato (cherry), 9 spinach, 16 leaf lettuce (to avoid being swamped with lettuce, I'm planting a row of four Grand Rapids, followed by a row of four Romaine a week later, then doing the same again two weeks after that; remember that with leaf lettuce you can select leaves, or cut it an inch above the soil and it will regrow until it starts getting bitter, so 16 plants is a lot for a small household).
Front row (l-r): 16 carrots (actually 15, due to the 2x2 in the corner), 5 marigolds (to keep butterflies off the lettuce and spinach), 4 bush beans (again, to stagger the harvest I'm using one green and one yellow, followed by another green and yellow planted two weeks later), 1 chives (both as an herb and as a pest repellent).
So you see, even a small garden like this can yield a lot of produce. And it's all about rotation too, so once the carrots run out, a fall harvest crop like broccoli could go into that same space. I happen to have a fairly big yard, but I know the compact size of this type of garden is great for urban gardeners as well, who might otherwise not have the space for a huge row garden or might have to suffer questionable soil conditions.
All told, this project ran around $200 (I'll update when I dig out all the receipts), with the soil actually making the most expensive component. But it's in, and should pay for itself for years to come. And it took two days to build, two days to fill (due to the weight of the soil products, remember), and a day to stain. Really, it could have been completed in about three days if I had a truck to move soil and didn't have to wait for a weekday to avoid having a stain-covered toddler. So a quick, cheap, and simple build that will bring years of satisfaction. Sounds like a good project to me.
Time for a cold one.