I used wood for many years. The best I got out of them was 4 years no matter what kind I used. I absolutley refused to
build any more beds for frustration of seeing them go
kaput on me. I now use concrete blocks. 5 years and going.
These things will outlast me!

Tom

Yeah, I have no illusions that wood won't last forever and I expect to have to redo it every so often. However, we feel that materials like wood would maintain the look of our property best. (For the same reason I built my bat house using a pressure-treated wood pole rather than a steel pole...)

I also have this idea in my head that disposing of wood (chopping it up, maybe burning it in my fireplace or just "smuggling" it into the trash in bits makes it easier to get rid of should I want or need to tear it all down in a few years. How I'd get rid of a bunch of bricks or cinderblocks (or tires, yadda yadda) other than hiring someone to take it all to the dump, I don't know...

Thanks

Mark

On how to set the posts, I've seen some tutorials on building sandboxes that show that. Basically pick your corners and measure cris-cross to square off the bed, then dig the holes fo the posts, then cris-cross measure again as you tamp in the posts to adjust as the posts go in. Do not use concrete, just pack the dirt back in. Use a level when attaching the frame boards to get them even around the top, then add a second board as necessary - the uphill side might just need one board with the rest of the bed below grade.

When building on a grade, I've yet to find a way to build a bed that didn't involve digging into the grade on the uphill side and using that to build up the downhill side level.

Pardon my ignorance, but in the mini-post design how does one attach the boards to the posts? Put screws in at a 45 degree angle from the inside through the boards to the posts? That's the other thing that makes me a tad bit nervous about the 5/4" cedar is that that's not too thick to drill through at an angle.

(My expertise is more with technology than with outdoorsy stuff :-) )

Thanks

Mark

For the best durability, the posts are going to have to extend to the top of the bed.

For the basics on this sort of construction, look at:
http://www.diynet.com/diy/diy_kits/article/0,2019,DIY_13787_2274670,00.html
or
http://www.lowes.com/lowes/lkn?action=howTo&p=Build/BuildSandbox.html&topic=howToLibrary

I built my 4'x4' beds using cedar fence slats. To insure I had strong corners, I cut the slats 55 1/2 long. I then cut notches half way through each slat 3 3/4 inches from each end and placed the 4x4's outside the squares not taking up any space inside the bed. This worked so well, I added other slats to make the beds about 11" deep. All I had to do was cut the 4x4'corner pieces longer. I cut the 4x4s longer based on the length I need to level the beds with minimal digging.

I'm sure description is confusing, but I hope it helps.

Mark,
I used standard 2x10's, cut them to size, and then coated them with warm boiled linseed oil. I let this dry for a day or two before assembling. To assemble, I drilled counter bored holes and bolted the boards together with 3/8 x 6 galvanized lag bolts (make sure your end boards are 4'-3" to make up for wood thickness). The counter bore is so the bolt heads don't stick out. I then layed the box in the place I wanted it and used marking paint to outline the box on the ground. Next, take a flat blade shovel and shave off the grass to get the outline level. (My area is about 5" out of level over 10') Once the box was level and in place, I drilled holes on an angle thru the side walls, right near the ground, and drove 10" landscape nails thru the box walls to pin the box to the ground. Last step was to shave out all of the grass inside the box and then fill up. I know these boxes will last 4 to 5 years without any other treatment, maybe longer. When they begin to fall apart, I'll dig them out and drop a new one in place. I figure if the soil is moist, it won't fall apart when I remove the old box.
Good Luck,
Mike

I am designing some raised beds, also, and have found several companies selling plastic anchors and corner brackets designed to hold 2x6 boards. You might check out:

http://www.burpee.com

htttp//www.parkseed.com

http://vegherb.com

http://www/backyardgardener.com

hppt://www.raised-garden-beds.com

In fact, if anyone has experience with any of the "plastic timber" systems, I would appreciate your comments. I'm reluctant to add plastic timbers (isn't that quite the oxymoron!) to my backyard landscape for fear it will look phoney, but some of these materials come with a 5-year warranty, which would surely outlast real wood.

Thanks and good luck!

My raised beds are made of untreated 2 x 6's, two beds stacked on top of each other to make them 12 " deep. Since our beds are 36 feet long, we use 2 x 6 x 12's and you know all wood is not straight.

Therefore, for support, we pound pieces of electrical conduit into the ground on the outside of the bed, about every 10 feet and use those connectors you can purchase that fit around the pipe and have pieces that extend on both sides of the pipe with holes in them. Screw these connectors to the bed.

Hope you can make sense out of this. The untreated wood lasts aproximately 5 years. If you use wooden stakes instead of pipe as the support, they will rot, believe me.

Last summer, weeds got the better of me and my raised beds so this summer I converted my garden to 12, 3'x8' raised beds using 2"x10" ACQ. I just layed the boxes on my existing garden soil and dug them in enough to get them level (at the most 2 inches). I used landscape screws in lieu of galvanized landscape spikes. The screws are 6 or 8 inches long with a square head for driving with a drill driver that comes with the screws. They are a bit more expensive than the spikes but much easier to use when assembling the box corners by yourself. If they frost heave this winter, I will stake them with some rebar driven down through a vetrtical hole in the boards.

Hi Roongarn and the group, I just made a large raised bed myself and learned a lot in the process. I have some nice pictures of the whole project from start to growning my first plants. Check out the link below and follow the links all the way back to the start.

Next spend some time at:
http://www.raised-garden-beds.com/

There are some very nice production raised beds to look at, maybe buy some or give you ideas on how to make them. There are also some great landscaping ideas.

Regarding what wood to use, down in central florida my choices are more limited then yours. Untreated pine is out of the questions as it will rot in as little as 1 year down here. I'm sure untreated cedar would do much better and I considered using it but in the end because of the size of my bed I decided to go with ACQ treated 2x6 lumber to cut down on costs. Notes on treated lumber, because of the rot factor I face I spent some time researching the different treated woods. I don't think you will find any CCA wood except for maybe dock pilings. CCA contains arsenic - that's why it lasts for years even in water!

ACQ does not have any arsenic in it. ACQ stands for Alkaline Copper Quartermary (not sure I spelled that correct). It should not pose a leaching problem when used in a garden. Please note that there are different levels of treatment used with ACQ. .40pcf is for ground contact, .25 pcf if for above ground. I tired hard to find .40pcf for all the wood but I could only find it in the 4x4 corrner posts. The 2x6 I used had the .25pcf. I'm hopping I can get 5 years out of it. Down here Florida Root Knot Nematodes are a huge problem so I would not even consider building a raised bed without a liner. I feel that installing a liner at least 2 feet deep on the sides of the bed should go a long ways to keeping the RKN from coming in from the sides during a heavy rain. The liner will also help make the wood last longer by keeping the moist soil on the inside of the bed from contacting the wood. Another note on ACQ, I found there is also a water repellent version available. That is what I used thinking that it should help make the wood last a bit longer - 6 years???

There is another treated wood in wide uses called CA -B. It does not contain any arsenic. I believe it uses something like Copper Alkaline Borate. I did not spend as much time reasearching this blend but I think the Borate might be a bit better against termites. I have run across Borate only treated wood for used indoors to keep the termites away.

More notes on treated wood, do not burn it! Do not try to use it or the saw dust in a compost pile! If you want to use saw dust make sure it comes from a saw mill that cuts the raw trees. Not from some unknown source that might have mixed in some treated saw dust.

Regarding liners, my next small bed project will use Tri-Flex roofing underlayment. I found this at Home Depot and it is a very tough plastic that would make one heck of a liner. The next bed I make will use external 4x4 corner posts instead of having them on the inside. This will make instaliing the liner much eaiser and should make the bed look even more interesting. I will also use standard 3 tab roofing shingles installed upside down on the inside of the frame as a kick plate to try and prevent damage to the liner and to make a nice looking inside of the bed where the liner is above the soil.

I hope this helps, DC

Here is a link that might be useful: Big raised bed project (with pictures)

Hello, Roongarn

I built my beds from 1 x 8 rough-sawn poplar purchased from a local sawmill. I then coated them with linseed oil. They have been in place for almost a year, and the only thing I am noticing is some warping of the boards. They are weathering nicely. Hope to get maybe a couple of more years out of them. I even ripped some of the boards to 1 x 1 and made my grids from them.

If I were to do it differently, I would use the 2" thick boards to cut down on the warping.

TheBug

I use untreated 2 x 10. Period. I line the bottom with corrugated cardboard and get great weed supression for about two years. I decomposes and all is fine. I have 4 4 x 8 raised beds, 4 4 x4 raised beds and one 4 x 4 raised bed made of cement block. They work great. I try to keep things s simple as possible as I am no great shakes as a builder.

Here is a link that might be useful: Rural Life 2.0

Can anyone tell me how much compost, vermiculite, peat moss I need for a bed 4ft wide, 8 ft long, 10" high.

10" = 0.833'

4' * 8' * 0.833' = 26.67 cu. ft.

Call it 30 cubic feet to allow for the often dramatic initial settling after you've watered it in and let it set for a week.

Stuff bought by the bag should have the cubic volume (or you can compare to similarily sized bags of other stuff that does have a volume measure). IIRC, the typical bag at the box stores contains about 2.5 cubic feet of compost. So 4-5 bags of compost, a large bale of peat moss, and however you manage to find the vermiculite/expanded shale/whatever to fill out the remainder.

I have figured out a unique way to join the corners of my square foot garden beds. I use 1 1/2" PVC pipe.

I am enclosing the link.

Here is a link that might be useful: Garden Corners

Beeziboy, you did use the grey electrical PVC, right? The white or cream water piping doesn't stand up to sunlight; will begin cracking.

I used the white PVC pipe corners for 3 years now and have noticed no cracking.

When a new home would be under construction, I would stop in and get acquainted with the plumber on the job and asked for any old PVC scrap he was discarding. He always told me to help myself to anything under a foot long.

I have googled PVC manufacturers and asked the same question. They responded that the pipe is now manufactured with a UV inhibitor in the pipe as it is stored outdoors and must resist the sunlight.

I have no idea how long it will last but is easy to replace if necessary.

I stack 2 rocks on the ground and put one on top of those around my raised bed. It's like a mini pyramid, all the way around, and it's a good way to get rid of my thousands of rocks.

i'm sure cinder blocks work pretty well, but one downside for some of us is that they aren't thin enough, like wood. for those of us who have small yards, with a garden plot where every single INCH counts, they sure take up a lot of room. otherwise i would be happy to use them.. i don't mind that "industrial" look.

I've used the recycled plastic "lumber" for a flower garden in my front yard, where it was important that it look good. It's neat, easy to work with, the corners are nicely rounded, you can't get splinters from it, and there's no risk of termites. My raised bed could outlast the house. The kind I got is grey, the same color most wood decking turns when it's weathered a year or two. Since I have grey trim on the house, it looks fine, and I think it would be fairly unobtrusive with most color schemes. I believe there are brands that come in other colors, like dark brown. The main problem with it is the expense, but given that it will outlast anything, including cedar, I think it's worth it, at least for places where appearance is important.