Need alternative to pressure treated 4 x 4's for raised beds

[aquarose]

Now I am all inspired to make raised beds. Home Depot has a cheaper version of Trex called Veranda, $15 for an 8 foot board. But what do I use for the posts in the ground? I really want to stay away from pressure treated. Any ideas? Could I put sections of the Trex/Veranda vertically in the ground, set in quickcrete, and then screw the sides onto that?

 

[patandchickens]

Cedar (or redwood depending on where you live) is the traditional choice. It is pretty good'n rot resistant. It's what people usually use for farm fenceposts. Cedar is quite renewable and plentiful -- I have no idea about the status of redwood timber these days, you'd have to look it up if you are out west and are considering using it. Highly recommend cedar. Does cost about 2x+ as much as pressure treated lumber, but probably roughly comparable to trex.

And unlike trex, there is no plastic in cedar or redwood But, that said, it's not obvious to me why using trex or trex-like products as you suggest shouldn't work. Trex is more bendy/flexible than wood, but for such a short post as would be supporting a raised bed corner I wouldn't think it'd be problematic. You will need a reinforcing vertical on long sides at a shorter length with trex than you would with wood, fwiw.

You can also use well-banged-in T-posts. But they are not as secure, and just a bit of a safety hazard unless the tops are well hidden under wood.

Pat

 

[aquarose]

You will need a reinforcing vertical on long sides at a shorter length with trex than you would with wood, fwiw.

Hey Pat, thanks for responding. I was hoping somebody would think the Trex as a vertical would be a good idea. When you said I would need a reinforcing vertical on long sides at a shorter length did you mean that, instead of having one vertical support halfway on the long side (of a proposed 4' x 8' bed), I should have two or more? For an 8 foot side this would mean one every 32 inches, or even 24 inches? Thanks.

 

[patandchickens]

When you said I would need a reinforcing vertical on long sides at a shorter length did you mean that, instead of having one vertical support halfway on the long side (of a proposed 4' x 8' bed), I should have two or more?

Oh, sure, if you want to put it in comprehensible, plain grammatical English, yeah that's what I mean <laughing at self>

I can't give you numbers, I just know that trex is flexier than wood. (I know someone who made the mistake of building all the box stalls in a LARGE new horse barn out of trex. Of course, as soon as the horses started leaning on and kicking the stall walls... )

I'd just sort of take one of the boards and experiment with different bracing intervals (with the board just lying on pieces of wood or whatever on the ground) til I found the largest interval that seemed to be fairly rigid. The higher your raised beds, the more it matters. As soil settles over time, though, it can exert some pretty meaningful pressure, and you don't want to end up with odd bulgeing waistlines on your beds

Have fun,

Pat