Though we are most probably not about to adopt a raised bed design that is as involved as my theoretical one, I have been turned on by the idea of a keyhole garden based cul de sac to increase growing space and improve efficiencies. If the path into the center of the bed is 2 feet wide, the bed itself can be 10′ x 10′ and still have every part of the growing area accessible from a path, a new typography for raised beds.
My design for the raised bed has been largely determined by choice of materials. From a recent Craigslist run, we obtained a dozen large shipping pallets and have been breaking them down to individual boards, a variety of 2″ x 4″ x 6′ and 1″ x 4″ x 3′. The quality of the wood is generally poor and prompted me to think about adding extra structural supports that were externally located. This way, the force of the soil pushing against the wood would act to push the 1×4′s against the 2×4 supports instead of popping them out.
Since the completed raised bed would be an unwieldly and heavy 10′ by 10′ I designed it in sections that could be screwed together at the final location.
I’ve built it over winter and have set it in place with a layer of hardware cloth to stop the gophers, cardboard to block the weeds, and lined it with 3mil black plastic to see if it would extend the lifespan of the wood. I reduced the dimension to 10′ x 9′ so that it would fit better in the yard. Otherwise it was built pretty much to design.
In it we dumped the sweetest black compost I’ve ever had the pleasure of smelling that was available for cheap from our city’s compost facility. We hauled in almost 5 yards of it at the cost of $30.
Because we wanted to evaluate the Back to Eden approach to gardening, we also added 3 inches of screened and semi-decomposed wood chips as a mulch layer.
Ally had recently got a free 4′ x 8′ raised bed on Craigslist from a person that was moving. This I also assembled, along with a tiny 2′ x 3′ bed I improvised from some old fence posts laying around in our wood pile. At the bottom of the 4′ x 8′ bed I laid rotting almond logs, my tiny foray into Hugelkultur.
So far so good, now to get growing!