How to build a raised garden bed
Here's an easy tutorial on how to construct your own raised garden bed in five easy steps.
Raised garden beds in Seattle. (Photo: RJL20/Flickr) 
Three important considerations to keep in mind when picking a spot to build your raised garden bed are light, level ground and ease-of-access. Picking a flat, not-too-shady location (the spot should get at least 6 hours of sunlight per day) will require less effort (e.g. digging) on your part and help your garden grow to its maximum potential. Don’t build directly under trees or too far away from water sources. For maximum sun exposure, orient your bed in a north-south position. If you plan on building multiple beds in a row, make sure there’s ample space, at least 2 feet, between them for you to maneuver.
In terms of size, a bed three or four feet wide is generally considered a good place to start so you don’t have to step into the garden or strain yourself reaching across the bed. The minimum depth should be 6 to 8 inches although you can go as high as 1 to 2 feet. How high you should build varies on the condition of the current soil (the worse off the higher you should go) and the kind of plants you plan on working with.
By far, rot-resistant lumber – cedar and redwood are fine choices – is the most popular building material for raised garden beds although some folks opt for other materials for aesthetic reasons such as bricks, concrete blocks, driftwood and tree limbs and recycled plastic composite lumber. If you plan on growing edibles, avoid pressure-treated wood and railroad ties as they may be treated with toxic chemicals. Many lumber centers sell Forest Stewardship Council certified lumber. If available, go the FSC-certified to give your green space some extra green cred. Plus, if you purchase your wood at a lumber center and you know you exact measurements, they’ll cut for you in you aren’t too handy yourself with a saw.
After taking the appropriate measurements and assembling your lumber frame using a drill and exterior screws (it’s easy as that), dig a 2-inch deep trench in the spot where you plan on installing your bed. Position the frame into the bed, backfill the soil and make sure that your frame is firmly in place. Use a level to ensure that the frame is level all around. Inside of the frame, remove any trench and weeds, loosen the soil and add a thin layer of gravel to improve drainage. Next, line the bed with a layer of landscaping fabric or newspaper that will help keep aggressive weeds at bay. Or, line the bed with a layer of chicken wire that will prevent burrowing pests from popping up in your new garden.
With your frame standing and the drainage-improving, pest-preventing bottom of the bed ready to go, it’s time to fill your bed. Feel free to get creative here and add a customized mixture of topsoil and various soil amendments such as rotted manure, compost, sand and peat. Be sure to mix the amendments into the soil and not to bury it. Remember, if your native soil is workable, you can incorporate that into the mix to cut costs. Finally, rake the soil level, stand back and admire your handiwork. Now, it’s time to plant away!Comments
I am using non treated douglas fir in Tucson and a green product called cedar shield to preserve the wood. http://www.tucsonraisedgardenbeds.com
This scares me, it sounds too easy for this brown thumbed gardener.
Very good point about how raised beds allow you to control your soil. We built our raised garden bed recently and wrote up a step-by-step guide on how we did it: http://www.greenlivingeco.com/build-a-raised-garden-bed-how-to/
I find it amusing that some will cover their produce with herbicide and pesticide, but have issues with pressure treated lumber.
we live in midtown atlanta and put in five 4x6 beds last spring. we were re so happy with our first-year results, having now enjoyed 12 months of produce that, in the past, would have cost us a fortune!
as of today, the winter greens are in full form (kale, spinach, chard, lettuces, arugula), and we just added more spring greens, along with shallots, leeks, cabbage, broccoli and cauliflower.
we also have a huge kitchen window box dedicated to herbs that's been exploding late.... More
I would just like to caution folk that toxicity may be leeched from your choice of materials put to use for your raised bed systems...
I'm going to put in four 4' x 11' x 1'-high raised beds this year, looked at the prices of cedar, etc. and saw it was too expensive. Since I have two degrees in Chemistry, I thought I'd look into why Pressure Treated Lumber is bad. A Google search of "pressure treated lumber environmental" turns up a lot of articles on CCA or "Chromated Coppper Arsenate" pressure treatments.
As it turns out, chromated copper arsenate was phased out in residential applications at the end of.... More
