Green oak for raised beds

[Schroeder]

Cedar is sooo expensive I can't afford to use it to make all the raised beds I want. A local lumber yard tells me, "green oak works just as good, maybe better." It is priced at 90 cents a board foot. He said farmers use it all the time for everything from animal pens to horse troughs. I had never heard of it.

Is this lumber okay for ground contact? Are there any leaching issues I should be aware of? Has anyone here used it for raised beds?

 

[Rosalind]

Yes, oak works fine. We have oak sills on our house, which rest directly on dry-laid rock about 12-18" off the ground. Lasts about 100 - 150 years, unless you somehow get termites. Ask me how I know...

Green oak is just uncured, so it will be heavy. You don't need to use kiln-dried lumber if you're only using it for garden beds. No leaching, it hasn't been pressure treated. I don't think you could pressure treat it, really.

Your problem will be lifting it (did I mention it's heavy? it's really REALLY heavy compared to softwood) and running through drillbits. Instead of the usual whack-enough-nails-in-it'll-be-OK method of garden construction, you will have to use steel brackets and screws, and you will have to drill pilot holes for the screws. If you just use regular screws, the weight of the boards + the warping from moisture will rip regular wood screws right out. Nails, forget it, you'll be pounding the live-long day and you will break an entire box of nails just to get one through a board. Metal brackets and screws with pilot holes for the joinery, that's the way to do it.

 

[journey11]

Rosalind is right about the screws and pilot holes, etc.

Our old 2 story farmhouse, built in 1942, has 2x8" roughcut oak floor joists. They are indestructable!! You cannot hammer a nail into them at all, you have to drill first. Plus side for using them for raised beds--they will last a LONG time. Downside--you will probably burn up a lot of drill bits trying to get them assembled!

 

[mandieg4]

That is what we used. DH cut down a couple oak and poplar trees last summer and a guy he knew brought over a small saw mill thing and cut it into lumber for us. We used the outside edges to make my boxes. They really were a bugger to pound nails into. The biggest problem though was we didn't let them dry first and they warped over the winter. Not too bad, but enough to be be noticeable. One warped enough to pop the nails out in one corner. Brackets would have been better, but we were trying to do it without spending any money.

 

[Schroeder]

Well, so much for keeping the cost in line. Have you ever priced L brackets? They'd cost me more than the lumber. I wondered about the warping issue and you all have confirmed this as a problem. My wife really wants me to install 14 raised beds each 4 ft x 10 ft. I priced out the green oak at around $300. That doesn't sound too bad realitive to the cost of cedar but add another couple hundred dollars for brackets and OUCH!

 

[Rosalind]

Oh, yeah, 14 of them...I thought you were talking about, you know, a smaller number. If it's only a single-digit number, then it's not so bad, adding about $10/bed isn't horrible. But yeah, for that many, you might as well go ahead and get the cedar. Plus, for fourteen, you should count on wearing out or breaking at least two drillbits. Am not kidding.

 

[lesa]

Remember, you really don't have to surround a raised bed...I very often just make a raised area and plant it. I keep the grass trimmed around them and they look very attractive. If the purpose of the raised bed is to plant in "new, better" soil, you really can just put it somewhere and plant. In my yard, I have done kidney shaped and in the veggie garden, I just do long, raised rows. Just a thought....

 

[patandchickens]

Seriously, unless you are trying to make VERY raised beds e.g. for wheelchair gardening, there is just NO reason you need to surround them with anything at all. Just hill the dirt up and dress the edges periodically and it will be fine. You can line it with pavers or rocks or concrete rubble slabs if you want fancy (although this is also a bug-and-slug-and-weed-root refuge), or put wooden surrounds around as many as you can afford and leave the others plain until another year or a winning lottery ticket comes along

Good luck, have fun,

Pat, who would rather chew off both feet than deal with that much green oak!!