Materials for raised garden bed walls

In my area of Tennessee we have clay soil which is not conducive to raspberry growing, so my solution is a raised bed. I want to build a 8 ft x 4 ft about 20 inches high. I'm looking at options for materials ... pros and cons.

Pressure treated wood - will last longer, but I understand chemicals can leach into the soil. If the inside walls were lined with heavy visqueen, would that prevent the leaching?

Regular wood - would rot

Composite deck boards - I know this would last, but would it leach anything?

(I know there are companies that have kits, but with the size & height I want the $$$$ is too high for me.) Any input would be much appreciated. Thanks.

ewarchery: I've been looking at a raised bed also; but, want mine deeper than they want to sale and they are awful steep in price was thinking about making on myself also. Hopefully, someone will come and help us out with what materials to use. What medium are you going to use in the beds? I was thinking maybe jungle grow potting mix?
joy

joy112854, Haven't decided yet as to the medium/soil/compost.
I figure that we will get it built this summer, fill it in the fall or even winter (since ours are fairly mild. Stretching it out since it looks like spring is the best time to plant the raspberries anyway. And figure there is time for good research and input before jumping into this.

And I agree, I hope somebody can help us out with this!

Hi...here is a link that might be helpful...I am thinking about doing some raised beds also. http://www.sunset.com/garden/backyard-projects/ultimate-raised-bed-how-to-00400000011938/ hope this link works!

Somewhere here it's been posted that the new pressure-treated boards are not containing the hazardous chemicals anymore, and are perfectly safe to use for your raised beds.

Linda

The attached photo shows my combination compost/grow mix bin made from standard 6 feet long fence boards. The bed is 4x6 foot and lumber cost is less than $30. Each cedar fence board cost slightly less than $2 each in my area. They are only 5/8 inches thick compared to the standard dimension of 3/4 inches and most people say that is too thin but this particular bin has been completely filled and emptied numerous times during its 4 year lifespan and as you can see, it still stands square. I have used a minimum number of vertical braces but you could increase those for even more strength. The corners could be stronger if you used 2x4 inch or 4x4 inch lumber as cleats. I only used 1 1/4 wood screws but for more strength you could combine that with waterproof construction glue.

The cedar mellows to a nice gray color as you can see. Painting or staining wood to 'seal' it under flower bed conditions is a losing proposition. The wood should be allowed to breathe. It will absorb moisture under moist conditions and then give it back to the atmosphere under dryer conditions. It is naturally going to absorb moisture from the moist dirt of a flower bed. If you paint or seal the outside of the boards, you trap moisture in the board. There might be some type of stains that allow the boards to breathe but I cant name them.

I wouldn't recommend a plastic liner inside a bed as deep as you have mentioned building. Your grow mix needs to breathe too and supply oxygen to the roots of your plants. The bed pictured here is 22 inches deep, about the same depth you have mentioned. The small cracks between boards you see here allow excess moisture to drain from the bed plus allow air to the plants roots.

Jay: Cedar is expensive isn't it?
joy

Cedar "fence boards".........5/8th inch thick, 6 inches wide, six foot long cost about $2 each in my area. Only one lumber yard in my area sells fence boards that are 3/4 inch thick and they cost closer to $3 each. Once you get past the fence boards into larger dimension sized cedar lumber such as 2x6's, 2X8's etc then cedar becomes very expensive. Is your privacy fence a cedar fence? Or is it made from treated fence boards?

Jaywhacker: Treated fence boards.
joy

Jaywhacker,
thanks for all the valuable input. Since the plastic is a big "no", what would you think for some type of gardening fabric? I want to minimize dirt loss from between the boards.
Thanks.

I dont think you will lose any grow mix thru the cracks to amount to anything. Especially if you use a fairly course mixture of faster draining material as a grow mix.

I have used weed cloth in the bottom of raised beds. The roots of some of the more aggressive plants will grow right through it. I have had butterfly bushes, mexican marigold mint, and some syrian oregano grow right through it. I think your razzberries would do the same. Since your grow bed is a ground bed, an organic growing system, I think I would prefer to leave it open to the ground so the earthworms, and various ground squigglies could assist in whatever it is they do to improve an organic ground bed. Of course if you have gopher or mole problems, you could use open mesh hardware screen to keep them out. Weed cloth wont do you much good in controlling weeds either. Weed seeds just blow in on top of the bed and sprout there anyway. But if your bed has a nice fluffy grow mix, the weeds just yank right out of there, roots and all, not much labor involved.

As you can tell, I have mixed emotions about the use of weed cloth. About the only way I use it anymore is to try to prevent grass and weeds in places where it is difficult to mow. In the attached photo, I have weed cloth under the raised platforms I built for stacking containers. And that is the more expensive kind that will actually last a few years and actually does block growth under it. That little haze of green near the base of one platform is a ground cover called "frogs fruit" which is very common in this area. All the rest of the frogs fruit in that area went brown and dormant as the spring rains ceased and the summer sun hit it. With a little rain (or a sprinkler) that stuff will start growing again. And what amaze's me is that it will continue to grow even under some weed cloth, will lift the weed cloth up 6 to 7 inches high while growing under there. I will show you a picture of that in the next post down.

This was a low section of the yard that stayed wet and frog fruit grew rampant here and was often too wet to mow. So I covered it with weed cloth about 3 years ago. Surprise, surprise!! Frog fruit grew just great underneath there and as the cheap weed cloth developed little holes it would pop up thru there through the hole and spread out and enlarge the holes. The hot summer sun is about the only thing that can control that frog fruit. I dont know why I haven't removed this mess. I guess I am just enjoying the battle between the frog fruit and the weed cloth.

Jaywhacker, my weed cloth is the cheaper kind and it now has holes all in it, had to double it this time when I placed it under my lay flat bags for my melons, you got quite the garden there. I've learned quite a bit about gardening and what to use and what not to for next time; but, I do so want a AWS, needing directions for that as I want one on a timer for watering my EBs and HEBS 3 times a day, 5 mins each, my daughter is going to do it for me, if I can get a list of things I need and how to do it in steps she can follow. I'm also looking round for another garage sale table and will probably buy about 10 more authentic EBs for next time and use these HEBs for patio plants as in fruit trees.
joy

Since it is over a hundred degrees outside and too hot out there for an old codger like me, I will just keep on talking about frog fruit. Some of you might find it interesting. It is a native ground cover in this area. When it is kept mowed, it makes a pretty nice looking lawn.

When I first moved in here about 9 years ago, I really cussed that stuff. I didn't know its name so I called it 'water weed' cause as long as the spring (or summer) rains fall, it grows like mad. Most summers here are pretty dry and hot and it just dies back and goes dormant as summer hits........most summers anyway. The good thing about having a lawn of frogs fruit here is that your lawn will turn a nice toasty brown during the hot weather and you wont have to mow. Unless you are dumb enough to water it........then you have to keep mowing it all summer. It didn't take me long to decide that brown is beautiful and by late spring, I would start praying for the frogs fruit to start dying back and turning brown. If you sprinkle with just a small amount of water, it is possible to keep the stuff green without it growing very much and needing much mowing. I dont sprinkle. Brown is beautiful and besides, by not sprinkling, I am conserving water which is a scarce commodity here in central Texas.

The "Natives of Texas" nursery is about 3 miles south of where I live. I went down there one day and Pablo, the guy who runs the place, had a big pile of frogs fruit on a work bench and was transplanting it into 4 inch pots. I thought he was crazy but he said he had an order for a thousand 4 inch pots of frog fruit from someone in Austin at $1.25 each. He just scraped a bunch of it off a bank beside their roadway and was potting it up. You cant kill the stuff. As long as it can grab aholt of a couple grains of dirt and a little moisture, the danged stuff will grow.

Here is some info on the stuff.

http://www.nativesoftexas.com/Frog_Fruit.html

And here:

http://davesgarden.com/guides/pf/go/62730/

HI Jay,
Your "Frog's Fruit" (Phyla nodiflora) is related to our "Lippia" (Phyla canescens). I suspect this is the reason you can't kill it with a stick is the same problem we have with Lippia here in Australia

Jaywhacker: You know I gotta ask this, do frogs like the frogfruit? If they do, do you have a yard full of frogs? LOL
joy

Our temperatures have been triple digit for about 10 days straight now. Frogs and frog fruit are all fried. And I am feeling a little dried out myself.

I personally wanted nothing to do with any kind of treated lumber...just me I guess. Cedar in any kind of size appropriate to what I wanted to build ( 4' x 8' by at least 12 inches deep) was prohibitive. My solution was construction/cinder blocks. They actually were cheaper than cedar, but a lot of work. I have been pleased with the result and plan to build another two more this autumn. I learned how to do it with my first one and built a better one the second time around. Hopefully numbers three and four will continue that pattern. The picture shows the basic pattern. In a few days there will be additional pictures of what I have done on the post I started when I was building these.

I like the idea of cinderblocks. I bought the "E" book, "Cinder block Gardens" which had some interesting ideas. Since 2002 I have owned a little Plymouth Neon. I figgered if I needed a truck to haul something, I would borrow my Son's. But it was never handy when I decided I wonted something so I found a way to haull about any thing I need in the Neon. By putting down the seatbacks of the back seats, I can haul 8 foot long lumber extending from the trunk area up between the front seats to the dash. Heavy bath towells protect the cars interior. Of course the 6 foot long cedar fence planks fits easier and I have learned to build all kind of things from them. I can glue and screw two fence boards together and end up with 1 1/4 inch thick lumber that is stronger than the very expensive 1 1/2 inch lumber at much less than half the price of the expensive stuff. Awhile back I figured out how many cinder blocks I could haul in the trunk area at one time as I was thinking of building cinder block beds. But that is a project for the future. Looking forward to seeing the rest of your photo's. I like pitchurs.

You are right there, cinder blocks are really cheap at Lowes, is that garden stones you have on top and did you have to cement them on or just lay them on top of the cinder blocks? Fried frog legs hey? I have had them before, we are having fried green tomatoes and fried eggplant tomorrow.
joy

If you are only going to grow raspberries then I suggest you buid a raised bed with patio blocks that are 9x13 with the 13 inch side down. Raspberries sucke prolifically but they tend to be fairly shallow and having the bed this deep will reduce the amount of suckering outside the beds. I know!

fancy van: I'm planning on planting things like beets, onions, asparagus, lettuce, cabbages, carrots things that need to be deep I think.
joy

On top of the blocks are poured concrete retaining wall cappers. Seems to me that they cost a little more than the blocks, but they make for a little visual interest by contrast. Plus they create a place to set either oneself or one's hand tools, and more importantly where my wife was concerned, cover up the large holes and give things like wasps less of a place to build nests. At the present, all the blocks and the cappers are just set in place. I wanted to make this as multifunctional as possible. I am experimenting with some ideas of how to use the holes and will photograph that as well.

The cinder blocks seem to me to be a great idea - gives you a good place to sit when you are working also! Also probably easier to build - no nails!

My raised beds ( except for the raspberries are made from spruce boards. They have been in place for 6 year now and are still in good shape
Here is a partial view - there are actually 3 beds and the flower beds around the outside are also raised 1 board high.

Building the beds wasn't that hard of work, just heavy during the heat of the day. The trick is getting things as level as possible so that the blocks line up with each other. A rubber mallet came in handy. The first one turned out fairly well, the second one I applied what I learned during construction of the first, so hopefully my third and fourth will continue to improve. A design incorporating the ability to sit and work was something I had in mind for my father but never managed to do before he had to give up his house.

A picture of a cinder block bed in January I used for onions and garlic. This bed was built and planted last Fall. The hardest and most crucial part is getting the first tier level. I'm pondering putting 1 X 8 or 2 X 8 boards on top of the blocks.

Jerry

Texasrock garden: Wouldn't the boards on top of the cinder blocks be a bit cheaper than the builders blocks? That might be an excellent idea, couldn't help but notice the spray thingy next to the raised garden bed, is it permanent and on a timer?
joy

The same bed only with a second tier added a couple weeks ago.

When I first started stacking the second tier it became apparent that the first tier was terrible unleveled or out of whack. It was hard work lifting out the old blocks, leveling and then replacing the old blocks. It took all of a morning in the heat to get this job completed. But, once the first tier was level and in place the second tier went in place in about 20 minutes.

Joy, The spray thingy is my first attempt at a drip system. The drip part worked well. The Old Melnor timer is broken or else it works off water flow for which there was little considering the drip flow. Anyhow the timer didn't work so all I got was a good drip system. I just never removed the timer.

Texas: That raised bed looks great, what did you use for a medium? I was thinking about coconut coir or potting mix? Would that work?
Joy

Joy, The soil is a rose mix I buy bulk from a nursery that sells soils, rock and mulch in bulk. I filled the cinder blocks with sand I had left over from a construction job to keep nasty little critters from making the hollows their home.

Buying soil in bulk is so much more affordable than buying it in 40 # bags at the Home Depot like stores. I pay $40 a yard loaded in the bed of my P/U. The cinder block raised bed holds about 2/3 of a yard or just a little more after it packs down some and I back fill.

As far as what type soil that will work in a raised bed, as you know by now it's up to the gardener to adjust amounts of water and food to a plant type / soil type / weather combination.

Jerry

Jerry: I've been wanting a raised bed for quite some time and yours looks simple enough to make, I could always fill the holes in the cinders and plant herbs in there couldn't I? That might help with preventing bugs from attacking what's in my garden, or flowers for that matter. I would like to try planting asparagus, beets and onions; also carrots. I emptied out my corn today, man, those roots were right through to the reservoir. I got them thrown over in the vacant lot next to mine where all the shrubs are grown up, maybe the wacky wabbit will munch down on that and leave my garden behind the fence alone, he will if he is smart, let's put it that way right? LOL
YSIC
Joy

I have 4 raised beds made from landscaping timbers. Because they are along the drive coming to our home, I wanted them to be attractive as well as functional. I intend to build at least 6 or 8 more beds in spring of 2010. One will be exclusively for Raspberries.

pineviewplanter: Beautiful as well as functional.
joy

Cinder blocks look like they would make very stable walls even if stacked 2-3 high.

My beds have walls 8, 12 or 16" high, and the usable root zones go 3-12 inches below grade (depending on drainage and how deeply I amended the bed when I built it.

So I get by with cheap concrete paving stones stood on end, $1 - $1.25, or a little less during sales.

Their stability comes from leaning them inwards a few degrees, and from being only one-high.
They look good if you straighten up the leaners every few years. You might want to chink the corners with something triangular, or line those corners with heavy plastic cut from bags of peat or manure.

They are really easy to move around, so you can change the size or shape or location of beds on a whim. A spot might be a compost heap this year, and a raised bed the next year.