Raised bed planters have a number of advantages: the soil is loose and promotes better plant growth, you can mix your own soil and know what is in it, you can raise the bed to work at waist height, and you can keep weeds at bay more easily. Sound good? Here's a crash course on the basics of including them in your garden...
Whether you are raising your planting beds six inches or three feet off the ground, there are some things to keep in mind when building your raised bed planters.
- Soil
Soil should be lose, full of nutrients and drain well. Mel's Mix is a good guide for getting started with the right combination of ingredients. - Weed control
Before you build the planter, take the time to lay down a layer of weed barrier between the ground and your soil. As an alternative to purchasing weed barrier, you can lay down cardboard to kill the grass and weeds. - Construction
If you are building directly on the ground the construction of your raised bed planter will be pretty straightforward. The utilitarian approach is to use four pieces of 2"x10" untreated lumber that are about six feet long, some nails and four short pieces of 1"x1" untreated wood. Just lay the square out and nail the pieces together, using the 1x1s to strengthen the corners. If you are looking for something more elaborate, try out one of these ideas. - Raised bed planter with sitting edge
This Old House has a step-by-step tutorial on building a lovely raised bed planter. You can build it as high as you like. - Ready to build kits
Natural Yards has a variety of ready to build raised bed planters that range from the very simple bed to a vertical planter. - Pest control
Earth Easy offers a raised bed planter with a built in bunny screen that easily lowers to allow you to tend to the plants. Consider something like this if small animals are attracted to your garden.
MORE RAISED BED PLANTERS ON APARTMENT THERAPY:
• How To Build A Raised Bed in a Metal Trough
• Gardening Q&A: Alternative Raised Bed Building Material
• Build A Raised Bed In Less Than 5 Minutes
• From Seed to Garden: Claire & Aman's Raised Bed, Part 3
• A Raised Bed for Both Computer and Plant
(Image: Kolin Smith, This Old House)
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I think if you use untreated wood, you have to use cedar or similar rot-resisting wood. Otherwise, I you might be building another bed again next year.
If you're not the handy type, or don't have the tools to make your own, these raised bed kits work pretty well. All you need is a hammer and a screwdriver to put them together: http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&langId=-1&catalogId=10053&productId=202520884&R=202520884 We just installed one last weekend and it took about 5 minutes to put together.
I removed my untreated 1x10 wood boxes after 8 years (they were really far gone by then). However, I found I had nice raised beds that didn't really need new boxes built around them and never replaced them.
Laurie, can you elaborate on why it's so important to use untreated wood? Is the issue just with commercial wood treatment methods, or is even staining the wood problematic? Thanks!
Untreated wood matters because of the chemicals it contains. We are careful to use organic soil and organic farming methods and adding chemicals through treated wood seems like a bad idea.
It is a good idea to use cedar as it will last longer in an untreated state. We built raised beds last year out of untreated pine and they are still in very good shape.
I've seen some raised bed planters made out of concrete cinder blocks. They're relatively inexpensive, don't require much in the way of tools as they can be dry stacked, and they last longer than wood.
We used a product we found called the "M Brace" to build a few raised beds on our patio. They're simple steel corners that you easily slide boards into - no tools were required! Since we put our beds on a concrete patio, we also lined them with plastic (with a few holes punched for drainage) to help contain the dirt. http://artofthegarden.net/
Concrete blocks are not very cheap if you're buying more than a couple, I priced that idea out and it was pretty spendy, not to mention transporting them. We ended up going with Hardipanel plank siding, it's cement fiber composite boards, sold inexpensively in-stock at Blue or Orange. They even scored and snapped 8' planks into 4' legnths for me so I only had to screw them together as described above. The bennefits of concrete without the weight or price. They are holding up great, this is our third year now and the only damage took a lot of effort to inflict (my husband broke a water pipe and threw his shovel down in frustration, broke a chunk off) One note, because the boards are thinner than lumber they are more prone to bowing outward--our 4x8 beds required stakes on the outside-centers of the long sides to keep them from bowing out. A 4x4 bed wouldn't need that extra support.
Yeah, I'd really recommend rough cut cedar or redwood if you're going to do wood--it will last a lot longer. Lowes sells rough cut cedar but they won't cut it to size (I have no idea why--they said it's too hard). I found a lumber yard that would though--if you're in Dallas, it's called Ivey Lumber.
Check these out: http://shop.geoplanter.com/GeoPot-Self-supporting-Geo-Pots_c2.htm
We built our beds with untreated pine, and they lasted about 4 years before they needed replacing (which I just did last weekend, again with untreated pine because that's what my local store had and I didn't have the time to mess with sourcing something else). They do start to rot away at the bottom eventually, but ours are simple enough that they're not too much of an inconvenience to build every 4-5 years. We don't mess with the sitting edge or anything, just get 2x10s or 2x12s cut to length, then screw them together with a simple butt joint, although this time I did put a corner block in for additional support, as the butt joint will start to pull apart over time as the wood softens and the dirt inside puts pressure on it.
My people criticize "Mel's Mix" because vermiculite and peat moss are not environmentally responsible ingredients. There are less controversial options.