Lane County Extension Service Master Gardener John Fischer here with KLCC's Good Gardening. I've already explained my concerns about raised beds. Increased water use, difficulty in maintaining soil fertility, and the over use of non-sustainable materials - particularly old growth cedar.
But despite my lecturing, and maybe because of mobility issues, or horrible native soil, many people still put in raised beds. So today we'll talk about better ways to do an often bad thing.
Build your beds out of something salvaged, or re-usable. Urbanite- pieces of torn up concrete from an old driveway- is usually free. And with a flat top and bottom, urbanite stacks nicely and can be attractive. Concrete blocks make great permanent beds, and if you don't mortar them together, they can be taken apart and used elsewhere when you move away from the raised bed craze.
The same disassembly strategy is even easier with the linking cement blocks that can be used for beds, retaining walls and the like. I've seen the blocks on second hand sites for free.
Yes, concrete is a climate problem, but blocks made with fly ash have much less impact than a solid block, and new hemp and concrete blocks are close to carbon neutral.
Of course native stone uses only the energy for the truck- and you to move it.
If you love the look - the feel - of wood, use salvaged materials. I helped remove some rotting raised beds a few years ago and have used the top unrotted four inches as a hybrid garden border with some old steel roofing I salvaged. The steel goes into the ground and the wood with a slot for the metal to fit in sits on top.
I'm using the metal and wood edge around my garden to slow- not stop - weed roots from entering my vegetable space.
