Untreated lumber - Raised flower/garden beds

[brian]

I want to construct (2) raised garden/flower beds. Each approx. 8' x

7' 10-12" high. Everything I've read recommends using cedar or another naturally resistant lumber but all are relatively expensive and my budget for this project is limited.

I also want to avoid pressure treated lumber.

If I use standard pine for this project. How long would it typically last before it rots? How much would I expect it to warp?

I'm only looking for 4-5 years of life for these beds and would replace them after that if needed. Will standard lumber hold up 4-5 years in an outdoor environment?

Thanks

[Mo' Sawdust]

Yes, pine would last that long.

If possible use 2x stock, use screws in the corners, plus plug the screw counterbore holes.

Also, because of the length-width, put in some braces mid-way, or third of the way to stop the beds from bowing out. Alternatively, stake the bed into the ground.

If using glue along with screws, use an exterior or marine glue. The powder kind where you add water works quite nicely.

[Luigi Zanasi]

On 28 Feb 2004 08:35:30 -0800, [e-mail] (brian) scribbled:

Depends on where you live. I made some raised beds out of 4X4 rough spruce dunning in 1991. They were rotten enough to need repair last year & will need to be replaced in the spring. I also made some out of

4X4 doug fir the following year. No outward sign of rot yet.

I live in a semi-arid subarctic climate, and outside stuff is frozen half the year, so YMMV.

Luigi Replace "nonet" with "yukonomics" for real email address

[Rick Samuel]

[Leon]

Maybe, but in Houston it would last about a year or two. Termites or rot would get it quickly.

[Larry C in Auburn, WA]

Pine will last 4-5 years no problem. I live in the rainbelt so I should know... The boards will definitely want to warp. The inside of the boards are sitting against the moist dirt so they are going to be wet 100% of the time, the outside will dry quickly especially in the summer. Perfect conditions for the boards to warp. You might want to consider 4-5 beds instead of two and make each 3-4' wide. It's tough to plant, weed, and harvest in a bed 7' wide. Screw the ends together and because the boards are really going to warp you should reinforce the ends with metal corner brackets (just a 90 degree piece of metal screwed to the inside of each end and side).

[darrenkip]

Lining the inside with 6 mil poly will help. If you live in a dry area it helps the beds retain moisture as well.

[Mark Hopkins]

Why not concrete blocks? Easy to move/relocate and won't ever rot. Alternatively you could build a mold and pour your own shapes.

[Fly-by-Night CC]

Hailing from the Portland, OR area, I agree. I put in 2"x12"x8' beds of standard building lumber 4 or 5 years ago and have seen very little deterioration. When you think about our climate, the inside surface of the wood is likely wet 100% of the time - given the 7 months or so of rain plus the 5 months of watering the Fall harvest.

[Larry Blanchard]

If you do, be careful to check the soil alkilinity. The concrete will (if new) leach into the soil the first couple of years.

[Roy Smith]

I put in some raised beds about 4 years ago (had 5 yards of topsoil trucked in to fill them). I used 1 x 6 cedar planking from the borg. The exteriors still look pretty good, but if you dig down to look at the burried interior surfaces, there's a lot of deterioration going on already. I figure I'll get another 4 years out of them then they'll fall apart. I can only guess that pine would rot even faster.

This is my vegetable bed. No way am I eating anything I grew in pressure treated lumber.

BTW, if you buy dirt, you want to buy the best topsoil they've got. The delivery cost was slightly more than the purchase price. The cheap stuff doesn't cost any less to deliver.

[Jon Endres, PE]

I used untreated white pine for my raised beds in the backyard. This will be their third summer, and while they are grey and dirty, they haven't shown any overt signs of rot. I'd expect you'd get five years before replacement. I wouldn't use treated wood anyway. Now, if I could find enough black locust to make those boxes - I think they'd outlive me.

Jon E

[Wilson]

I've got planter boxes made of doug fir going on 3 years. Though I don't plan on staying in this house for very long, ( not enough shop space) I'll probably take them out permanently before I replace them. I think they got at least another 2 years left.

replacement.

[bob]

I'm getting ready to do exactly the same project. I'm building mine out of Brazilian redwood, which is not really redwood, but massaranduba. Three times harder than red oak and extremely resistant to rot. Used a lot for decking and guaranteed for 100 years against rot. I can buy it locally right now from a distressed merchandiser for $2 BF. I've got a sh*tload of it stockpiled.

Bob

[George]

Y'know, if you soaked lumber in the chemicals that make redwood or tropical timbers durable, I'd bet you couldn't clear it through the health freaks.

[Fred the Red Shirt]

If you can find paraffin cheap enough you can melt it in a double boiler and use it to seal the wood, or at least the side of it that is against the soil. Might make things last longer and paraffin is food-safe, unlike tar or creosote.

[D. Mo]

Makes sense. It's not the wet alone that rots it out but rather the wet/dry cycle. If it stays wet all the time it'll last longer then if its wet then dried out.