Do they truly need to be double height?

Well, they were double height last year and this year. They are filled with excellent soil, and most of my seeds have been planted.

The dirt in my yard is extremely rocky. I wanted to make absolutely sure all my plants' roots would have plenty of room to grow before hitting gravel, rocks, and smallish boulders. Probably I'm paranoid, since vegetable roots don't tend to be that deep. But that's why the raised beds are so deep.

Yes, I could hire someone to shovel out one height-worth of soil and spread it... somewhere (small yard). But I'd really prefer not to do that, if it's at all possible to stabilize the raised beds as they are.

I've considered driving stakes or rebar into the ground beside every "sag," but even thin plant stakes hit rocks before getting more than an inch or two into the ground. It's really a challenge to place them.

What are the dimensions of the bed? Would a board inside the middle of the bed connected to both sides work?

tj

The bed is 48 feet long and 4 feet wide. It was created by placing commercial plastic raised bed kits side by side along one side of my back yard. The kits were also stacked one atop another, the whole way.

There's a kind of wooden strap that attaches the tops of the beds across the dirt--at the top, not all the way from top to bottom. So it just holds the tops together.

I'd love to get some sort of board in there (its width equal to the depth of the soil), but it would need to be attached from the exterior of each bed... which seems impossible.

Finally took photos... You can see how each "bed" is actually two one-bed kits, stacked one on top of the other. The row keeps going... 12 4x4 beds in all. The farther from the ends you look, the more the top and bottom sides are bowing out from the pressure of the soil within them.

Below, you can see that the corners are stable (thus far, anyhow).

Hammer 2x2 boards down inside and screw them down. Those top wood supports aren’t helping the problem. They seems to be pulling the tops in.

Thank you! That seems like a very reasonable approach. It'll have to wait until fall or next spring, so we could shovel half the soil from each raised bed, in order to open up the interior to screw in the bottom horizontal pieces.

What a mess my friend created for me, with the best of intentions!

You could screw the bottom pieces in from the outside.

Good idea to use boards, maybe 2x2s, for structural support. But why put them on the inside? Put them on the outside, and then you won't need to dig anything out. If the planks are too thin to have good purchase on screw threads, just bolt the supports to the planks. You could do that NOW. Another advantage of putting them on the outside is that you won't have wood structural supports buried in soil.

Thank you! I'll mention this to my friend. And maybe he could somehow push the bulging sides in a bit while doing that. (I picture a gentle sledgehammer, but on second thought, that's an oxymoron!).

Makes sense! Thank you--I'll send this info to my friend.