AggieGrace
Newly Registered
Posts: 3
Joined: Tue Feb 12, 2013 10:10 am
Location: Vista, CA

Best lumber for raised beds

I'm sure this has been discussed ad nauseam, but we're going to be buying the materials for my raised beds this weekend and I'm going cross-eyed from researching everything. So, a couple of quick questions:

1. Treated vs untreated? I'm looking at possibly untreated redwood, but still unsure. If the big box carries cedar that won't bankrupt us, I'll do that, but I can't find it on-line, so I'm not sure they carry it or not.

2. Termites. I'm in So Cal and termites are a big problem here. I came across a brief mention in another forum that having wood beds will attract termites (makes sense) and then they'll find your house. We've already had to treat the house once when we bought the place, so not wanting to go down that road again. Are termites really that much of an issue? I've only ever heard that one comment on them.

3. Other materials besides wood? Concrete, perhaps? Still worried about the chemical contamination, though.

Thank you!

User avatar
rainbowgardener
Super Green Thumb
Posts: 25279
Joined: Sun Feb 15, 2009 6:04 pm
Location: TN/GA 7b

I build mine out of treated 4x4 pine fence posts, stacked. The fence posts are very cheap, the 4x4's last way longer than boards, which quickly warp and fall apart. I do not believe there is any problem with the treated wood, but I do seal mine, so that the chemicals stay inside and the wood lasts longer. Treated sealed wood is a lot less likely to attract termites. I've not seen any.

Concrete block or brick would also be fine and sometimes you can find that kind of stuff very cheap or free on craigslist, freecycle, etc.

gumbo2176
Super Green Thumb
Posts: 3065
Joined: Mon Jul 19, 2010 2:01 am
Location: New Orleans

The cost of natural woods like cedar, redwood, etc. that are rot and pest resistant is very high in most cases. I built my 4'x12' raised bed out of 2x12 treated lumber and screwed the corners together for a better hold. Modern treated woods don't contain the same chemicals that were used years ago. I've not had a problem with rot and I've had my box for almost 3 years now.

The only advice I can offer is if you plan on using treated wood, look for very straight boards that are air dried. I have a lumber yard near me that stacks all their treated lumber with spacers and they let it dry quite a bit before offering it for sale. Stores like Home Depot, Lowe's, etc. sell it as fast as it arrives and is often so wet when purchased you can feel the dampness in the wood. A lot of times when this wood dries out it twists and warps badly. That's why I get pre-dried wood and pick the straightest I can find.

User avatar
tomf
Super Green Thumb
Posts: 3233
Joined: Mon May 18, 2009 8:15 am
Location: Oregon

From what I have read the new treated wood is non toxic. I also talked to a represenitive of the treated wood industry about treated wood, and he told me that there are two kinds of treated wood, both are non toxic. They use copper in much of it as a preservitive. I have never had bug issues with treated wood, and it does not rot. You can also use a copper wood sealer over the treated wood for extra protection if you feel the need, I do this for posts going into the ground.
When you make your beds make them high enough so you do not need to bend over much, and make then so you can shake hands in the middle of them so that you can work the center of them with ease.
I do not do raised beds yet, I rototill and push the soil into mounds in the Chinese mound system, it is like a raised bed with out the encasement, only not so high. The mound system allows air to enter from the sides of the beds and keeps you from walking on the beds.

imafan26
Mod
Posts: 13962
Joined: Tue Jan 01, 2013 8:32 am
Location: Hawaii, zone 12a 587 ft elev.

I use hollow tile blocks and stones. Cheaper than wood. The stones were free.

I dry stacked the hollow tile. That way excess water weeps out between them. I use rebar to stabilize them and fill the holes with stones and dirt. They don't rot and they are still cheaper than buying wood.

Since I am not a carpenter and can't put a 90 degree corner together without using angle iron, it is much easier for me to dry stack hollow tile.

If you do use wood, you have to put in those corner stakes to stabilize the corners or they fall apart there first. I learned that the hard way too.

People said that it was sometimes hard to get around corners with a lawn mower. Use a weed whacker instead.

I have a small yard and it was hard to get my lawn mower over the paver patio, past sidewalks and over stepping stones. Not to mention it had a nasty habit of sliding down the slope in the front yard. My mower sits in the patio unused and I weed whack the the weeds and the grass. Some people are really good at it and can make it look very smooth. I just want to get it done so the swirls are clearly visible, but that resolves itself in a few days.

User avatar
jal_ut
Super Green Thumb
Posts: 7447
Joined: Sun Jan 18, 2009 10:20 pm
Location: Northern Utah Zone 5

I don't garden in raised beds, but I am a carpenter by trade and have seen lots of wooden things in contact with soil. It is always the same........ the wood rots out. Now if I were to build raised beds, I would use concrete.

The concrete blocks would last forever. I don't know what the cost would be compared to wood, but go price some concrete blocks and see what you think. The blocks are 16 inches long. To make a 4 foot by 8 foot bed would only take 20 blocks.

If you are inclined to build things, you could also form the sides with 1x8 wood boards then pour concrete in the forms using bagged concrete. Put a row of steel reinforcement bar in this and it would be very permanent. 4 1x8x14' boards would be enough to form it up. With 6 inch wide sides it will take 15 80 lb bags to fill it.
Last edited by jal_ut on Sat Mar 09, 2013 12:00 pm, edited 2 times in total.

User avatar
jal_ut
Super Green Thumb
Posts: 7447
Joined: Sun Jan 18, 2009 10:20 pm
Location: Northern Utah Zone 5

I know........ what ever you decide to do will likely cost some $$$.

What can you scrounge up? Know any builders? They often have left over stuff at end of job that just needs to be cleaned up. See any demolitions going on? Sometimes used bricks or blocks and lumber can be had from demo sites just for picking it up.

Having grown up on a farm the garden was always just a corner in some field that was reserved for the planting of veggies instead of hay or grain. That thinking can still work in our back yards. Just dig up a spot, mix in some amendments, and plant. Never mind making a nice neat border. This is the least expensive in the long run and the plants will do fine. In fact I don't suppose the plants care a whit about that fancy border.

OK, it is not time to plant here yet as the area is still under snow, but some of you may be able to get started now. Have fun!!!

ruggr10
Green Thumb
Posts: 352
Joined: Sun Dec 26, 2010 2:53 pm
Location: Brunswick, Maine

Whatever is free, that isn't pressure treated or a railroad tie.

gardenvt
Green Thumb
Posts: 302
Joined: Fri Aug 13, 2010 11:21 am

We used untreated spruce in spring 2010. Three of the beds are 10x2x8s stacked for a depth of 20" (easy on the back). Over the summer and into the fall, we added three 12" deep raised beds . We used 2x2s in the corners for added support as well as in the middle of the beds to prevent warping. So far, the beds have held up fine.

Your budget is the biggest factor. Remember, you can always add to it over the seasons. Preparing beds in the fall is a good time to get things going and ready for spring planting.

Bushman
Full Member
Posts: 14
Joined: Sat Mar 16, 2013 11:54 am
Location: Michigan

This year I will be using 1x10 oak planks. I got them from work for free. I don't have bug problems but eventually they will rot so I was thinking of building the boxes and then lining the sides with plastic and then filling them with soil. This may help preserve them longer. If I had the money I would buy treated 4x4s and build all my boxes with them.



Return to “Raised Bed Gardening”