All About Raised Beds
Raised beds are commonly used by vegetable growers. They can be temporary, made with farm machinery that mounds up soil (often covered with plastic mulch), or permanent using fixed walls and filled with amended soil. The links below refer to permanent systems.
The Noble Foundation in Oklahoma has an excellent resource on raised bed production. It is geared toward a larger scale than the typical homeowner, but there are excellent ideas to be found. It also covers season extension and how to grow using raised beds.
In 2010 the Inyo-Mono Master Gardeners did a public workshop on growing in raised beds. The Raised Beds Workshop Handout has information from that event. At another event in 2013 at the Bishop Tribal Elders' Garden we produced an updated handout: Raised Bed Gardening in Bishop .
If you live in the low desert you should really consider growing in raised beds. If your location has very high levels of salt, for example Tecopa, you have a few extra considerations to ponder before building. Please see this guide: Desert Raised Bed Ideas .
Several years ago Dustin Blakey came up with this plan for a raised bed made of lumber that minimizes cost and is easy to build: Plan . Since making it, it has been determined that using deck screws is cheaper and works just as well as 1/4" lag screws with washers. This plan uses six 2x6 boards and one 4x4 in 8' lengths. Assemble it upside down on level ground and then flip it over so the legs go into holes. Only takes a few minutes to build. It's easy to add hoops to support covers.
If you like more pictures and a different take on raised bed designs, check out Sunset's Guide to Perfect Raised Beds.
Common Questions About Raised Beds
How deep should a raised bed be? Actually, no one knows for sure. There is great variability in recommendations. In our experience, 10" to 12" is enough to grow anything. Going higher takes more materials, which are expensive to get in our area. But higher beds mean less stooping over. It is wasteful to build a nice, deep bed and only half fill it. Don't do that.
Is it safe to use treated lumber? Treated lumber now uses ACQ or similar compounds to treat boards. These contain no arsenic. If you are still concerned about using treated wood, or you follow certified Organic growing practices, then use a decay-resistant wood such redwood, an approved Organic preservative, or non-decaying materials such as recycled lumber, or stone.
Can I use railroad ties? No. Those are nasty.
Will I still get weeds? Yes. You may start off cleaner, but if you don't stay on top of weeds as they emerge, you will build up a seed bank of weed species. If you do not kill/remove bermudagrass before planting a bed, it will grow up into the bed. Maintaining a high (but reasonable) plant density will help control weeds.
Straw Bale Gardening
We are unaware of any commercial attempts at this system in the Eastern Sierra, but the system is old (even if the hype surrounding it is recent) and has been used successfully in the Middle East and Eastern Europe. It is gaining in popularity with gardeners in the USA.
Essentially straw bale gardening is using a partially composted straw bale as a growing medium. The advantages are low-cost and easy construction, as well as the ability to grow on top of any surface, even concrete.
In order to use straw bales, they have to be properly conditioned for use well before planting. This involves jumpstarting the composting process with fertilizer.
In our experiments, using smelly nitrogen sources such as fish emulsion attracted wildlife with destructive results.