How to Build a Wood Garden Box

If you follow our Facebook or Instagram accounts you have probably seen hints of my garden box project that we’ve been working on for the last few weeks. My plan is to have three 4×16 boxes for vegetables, plus 4 3×10 boxes for berries and grapes. We have a big yard so I have plenty of space! We couldn’t afford to do them all this spring so we are just doing them gradually. I asked my husband to write up a tutorial so that you can create your own garden boxes and just adjust the lengths for the size of boxes you want. Here’s his wood garden box tutorial!

While you can make these wooden garden boxes in any width and length you want, our example is 4 feet by 16. This will show you how to make the “seam” to piece together the long lengths.

Parts list

The basic parts you will need are:
11 – 2”x8”x8’ redwood boards
1 – 4”x4” redwood post
5 – 2”x6”x10’ redwood boards (if you are making rails)
1 – box 3” decking screws

Optional:
1- 7/16” drill bit (twist or spade, doesn’t matter)
24- carriage bolts, 5 – 1/2” long, 3/8” size, chrome finish
24- 3/8” washers
24- 3/8” nuts
(these are pretty, but just for 24 it’ll be about $35 for all parts. You decide. I got mine at Lowe’s, see picture at right)

Tools needed:
Miter saw (or capability to cut mitered corners)
Drill

	First things first. Decide now if you want the posts to go into the ground or not. I can tell you that if you have extended posts, you’re going to have to dig some holes. If no extended posts, no holes. Once the box is filled with dirt it will probably not be moving around much, but you decide how you’d like to do it. I had to dig holes, and I’m still on the fence about whether I’d do it all over again. (Jodi would say to do them, but she’s not the one who had to dig the holes … ) If you do extended posts, just take two boards, lay them up on the post, and decide how much length you’d like to have sticking into the ground below the sides of your box. I’d suggest 4-6 inches. Once that’s decided, mark, measure, and cut four posts. If you just want to have your box sit flat, the posts will be cut to 14-1/2”. (Yes, 2x8s are ACTUALLY 1-1/2”x7-1/4”. Don’t ask me how they’re getting away with that robbery!) You will also need to take two of your 2×8’s and cut them into four 4 foot pieces.
	After all posts and 4 foot boards are cut, lay out your ends as shown. These will be the 4 foot pieces you made, stacked on top of each other, and flush with the posts at each end. If you have access to clamps, use them! This will keep your post in place when you drill through it. If you don’t have clamps, just be careful to hold your pieces tight against each other so they don’t move around as you’re drilling. This would be a great time to have your kids all stand on the boards to hold them in place (kids AND boards). Also, I set the whole assembly up on extra post pieces I had (I was building multiple boxes) and this made it so that my drill bit didn’t hit concrete at the end but pass through the wood. You can set yours up or just have it set on something that the bit can penetrate so that you don’t ruin your bit.
	For my bolt holes, I drilled the ends in from the side edge 1-3/4”, and down from the top of the board 3”. You should end up with two holes into each post. Keep in mind that if you drill at an angle your bit might not make it all the way through, so try to line up straight. Once the holes are drilled, put in your bolts, and tighten on the other side. The nuts should be 9/16”. Now do the other side of the end, and repeat to get two identical box ends. This was the easy part. Ready for the trickier part? Now you’re going to do the sides.
	At this point you should have 9 2x8s remaining. 8 are going to make up your sides, and the last one is going to become the joint. This board will need to be cut into 4 pieces, all the same length that you made your posts. The tricky part (at least for me) in joining the sides was to get the joint pieces lined up and flush AND held together for drilling. I’m not entirely sure I got it perfect, maybe a stationary vice to hold them while I drilled would’ve been better. Anyway, you can see in the pictures how I ended up doing it. I drilled my holes 1-7/8” in from the side of the joint board, and 3-5/8” from the top of the side boards. Basically, I drilled at the halfway point on the boards, and halfway between the center of the joint and the edge. I drilled two at a time instead of all four at once because I couldn’t manage to get everything flush with so many pieces. Once you have two holes drilled, get the bolts in. I tightened them down, then loosened them enough that I could fit the next side pieces in. Then I got everything all clamped again, drilled two more holes, and bolted it all together. Tighten them all once you have four bolts in place.
	When you’ve managed to get both sides jointed, you can set up your ends with your sides and clamp them. I stood the ends up and clamped them to the side, then drilled. My holes on the sides are in 3-1/4” and down from the top of the boards 4-1/4”. This will center the holes on the post and keep your bolts from banging together with the ones that are already in the posts holding on your ends. Hold everything together, drill your holes, and bolt it.

Putting on the rails (optional)

Our neighbor had awesome rails around the edge of their boxes that we wanted to imitate. The rails look nice, and provide a great “seat” for you while you are weeding or harvesting your fruits and veggies. For the berry boxes we left them off for now and may decide to add them on later. it’s up to you if you want to do this part or not. It adds a little extra cost and time.

Get someone to help you flip the box over (unless you did non-extended posts) and grab your 2x6s. I cut the mitered end of each board first so that I could figure out exactly where to put the straight end. Plus, straight ends are a lot easier to figure than mitered ones. I lined up my rails so that the mitered edge went right down the corner of my box. Then I centered it on the side board. Once it’s in the right position, mark where the center of your joint is and cut a nice straight edge at that spot. I worked my way around the box instead of doing the sides first and ends last.

When you’re putting the screws in, make sure to measure in such that you put your screws into wood (not air) and get them centered up so that you don’t put splits in your pretty side boards!

To move the box, I’d suggest popping the bolts out of two opposite corners so that you carry it to its home in the yard in two ‘L’ shapes. I split the box at the joints and it was HARD to get the bolts to match back up through three pieces of wood. I think it would be easier at the posts.

Once you have your boxes in your desired location, I suggest giving it a little coat of stain to protect the pretty wood. You can get cheap stain at Home Depot that will last 1 year, but we opted for a more expensive kind from a paint store that should give us 5 years.

Last step is to fill your garden boxes with soil, compost, etc. We bought a truckload each of top soil and compost and are mixing them together in our boxes.

Happy building! Feel free to upload a picture of your own wooden garden boxes to our Facebook page if you follow our tutorial or make your own. We love to see how others do theirs too!