How to Build a Solid Raised Bed in Under Two Hours
Two people, two hours, one raised garden bed. This DIY project really did take less than two hours, and that includes shopping time at our local home improvement store. Here are our step-by-step instructions for how to build a raised bed in under two hours.
Preplan: 15 minutes
1. Keep it small. The length is the biggest issue determining how quickly you can cut and assemble the bed. Our finished bed is 5' x 2.5' and the 5' length meant we could cut and assemble the bed in our garden shed (garage-sized).
To cut longer board lengths, you might need to set up the saw and assemble the bed outdoors, which can slow things down a bit.
2. Write down the measurements so you know what lengths to cut the lumber. Decide what height the sides should be - you may need two rows of boards for tall beds.
If you don't have a saw, you could have the boards cut at the home improvement store. We wanted to cut ours so we would have exact measurements, and not pay extra for the cuts.
3. Decide where it will go. We had been eyeing the yard for a few months, so we already knew where to site the bed to capture the most sun. Clear out that space and level it, if necessary.
Shopping: 45 minutes
Living in the city has many advantages! We live two miles from a big box home improvement store. Once we figured how to build a raised bed, we made a materials list and did a quick in-and-out on a Sunday morning, before the crowds hit. We bought:
4 8-foot boards, sized 2" x 6"
1 8-foot length of 1" x 1" lumber
A big box of 2.5" deck screws
Some people don't want to use salt-treated lumber to build raised garden beds because it contains chemicals. I have done some reading up on this, and it seems the biggest problem is that arsenic is sometimes used in the wood treatment.
The studies I found concluded that a) not enough arsenic is used to leach into the soil in a meaningful way, b) any amounts that do enter the soil only do so right at the edge of the bed, and c) when plants do show trace amounts of arsenic, it's not nearly enough - even if eating an entire bed of plants at once - to affect a human system (arsenic leaves the body after a few days).
After reading these results I decided to use salt-treated lumber to build a raised bed because it's cheap and easy to find. Our bed frame will also sit outdoors to weather for a month before we add soil and plants.
Building: 45 minutes
Chef Iggy cut all the boards to size while I sat in my home office and worked on an overdue story. He's nice like that.
Once he had the boards cut, we found a flat place (the shed floor) to assemble them. Our bed has 12" tall sides, so we planned to build two 6" tall beds and stack them on top of each other.
We laid out the first level, butted up the boards at the corners, and screwed them in. Then we set the second set of boards on top of that and screwed those corners together.
Finally, we inserted the 12" tall 1" x 1" pieces at the corners and screwed those in. That way the two layers wouldn't separate.
When I say "we," I mean Chef Iggy did most of the work while I occasionally held some boards and made semi-helpful suggestions. Also, I took pictures. You could probably save significant time if you don't take pictures.
Finishing: 5 minutes
That's basically how to build a raised bed. Once finished, it can be placed anywhere in the garden. We lifted ours on its side, carried it through the shed door and out to our chosen space next to our fence. Chef Iggy leveled it, then pushed dirt and gravel up around the outside edges to seal the bottom cracks.
And voila! It's ready to go. We aren't adding dirt yet because I want the lumber to weather first, to give salt and other chemicals the best chance to rinse away. In March we will add soil and plants.
Now that you know how to build a raised bed, consider adding one to your urban garden. You can even use a similar plan to build a cold frame. It's an efficient and attractive way to get more from a small space.