This spring, I met an older couple that was picking up free pallets at one of the places I have gotten lots of pallets from for my gardens. I asked them if they make raised beds, and if so, how high they make them.
Turns out that the wife just had hip surgery and could not bend over without pain. They intended to use the full pallets to make raised beds. That would be a full 43 inches high. It was the only way she could continue to enjoy gardening given her health.
Evidently, I must have had a surprised look on my face because the husband quickly added that he had a tractor with a large bucket to fill the pallet high raised beds. He was just going to dig up a bunch of topsoil from elsewhere on the farm and put it into the new raised beds.
I asked him if he was going to use the hügelkultur method to fill the bottom of the 43-inch-high raised beds. He said he was familiar with the hügelkultur method but was not going to use it because it was just easier for him to dig up topsoil with his tractor bucket and dump the topsoil into the bed.
I was wondering what you were talking about "bury all the wood" but then I remembered that some people dig out a hole to put the hügelkultur wood in, and then top fill it with the soil.
I don't dig a hole in the ground to bury the wood in.
My raised beds are 16-inches high. I simply put my logs, branches, and twigs directly on the ground, without digging, and layer it on for the first 8-10 inches in the raised bed. Then I add an organic green layer of leaves, grass clippings, etc... Finally, the top 6-8 inches is a mix of high-quality topsoil and chicken run compost mixed 1:1.
I live on a lake, and my topsoil is full of sand. Nothing good really grows in that sand. When I say that I use a high-quality topsoil, I mean topsoil that I have to buy at our local nursery for about $50 a trailer load. Although it runs against my principles to pay for "dirt," the reality is that topsoil is worth it. Mixed with my chicken run compost 1:1, the cost per 4X4 foot raised bed is about $12.50 for the topsoil. Since I make my raised beds out of free pallet wood, my total cost, per raised bed, is still less than $15.00 completely assembled and filled with topsoil/compost, ready to plant.
You can certainly get some good deals on cull lumber from Home Depot. I would think, if you want that type of raised bed, then you could probably make a number of trips to Home Depot over the winter and get enough cull wood for your project.
Having said that, I make my 16-inch-high 4X4 foot raised garden beds from free pallet wood. Here is a picture of my most recent pallet wood raised bed, on the far left, before I filled it. It cost me less than $2.00 for the screws and nails used on that project.
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And a closeup of that same raised bed after I filled it....
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