You can get plastic boards. I don't know if Lowe's have them but Home Depot does. They look like boards and are make of recycled plastic. Or you can just work the dirt up to form the raised bed. 4 ft. wide X 10 ft. long, or bigger/smaller as you wish. They don't have to have a lumber border.

You also could use concrete blocks.

One of the major brands of recycled plastic lumber that Auther mentioned is called Trex.

Did you actually see termites or just damaged and/or rotted wood?

For what it is worth, I've had garden beds edged with lumber at our house here since 1999, and had them in Fort Worth for a couple of decades before that, and never have seen a termite or termite damage. We have fire ants though, and I think the fire ants must chase away or kill the termites. So, maybe all you need is a fire ant mound near your raised beds? (grin)

There are some organic solutions for dealing with termites, with one of them being the use of beneficial nematodes, which dwell in the soil and kill the termites. Some people have used Orange oil (the brand I use for other garden issues is made by Medina and is highly concentrated so I dilute it a lot and a $20 bottle lasts me years) to treat termite-infested areas.

You also could use a small amount of lumber to frame beds and build them out of metal. The Ardmore-based Noble Foundation has done research with this kind of bed, as well with some made from tires (which I never would use with edible crops because of the toxic materials that can leach out of tires). They also have done research with corrugated sheet metal beds, and I'll link that part of their website below. At the bottom of that page, there are links to lots of their other raised bed info.

If your soil is perfectly level, you may not need board edgings around your beds, but my land slopes and I have to have it or all my soil would wash away. Raised up mounds can work without edgings on fairly level ground, but you still could have erosion issues during periods of extremely hard rainfall. Mulching the mounded-up beds, including the exposed sides, could prevent most of the erosion.

Dawn

Here is a link that might be useful: Corrugated Metal Beds

Thank for the pointers.

@Auther: Are those plastic boards harmful / toxic?

@Dawn:
I did not really see any termites. The post fell broke in the bottom and it feels hollow; I just figured the termites are done eating and left.

Where do you get the orange oil? Is this the same http://www.amazon.com/Medina-Orange-Oil----32/dp/B00CEID4JU/ref=sr_1_1?ie=UTF8&qid=1414453962&sr=8-1&keywords=medina+orange+oil

I'm concerned with rust corrugated steel contaminating the soil? Thoughts?

Thanks!

Most wooden posts will rot, even without termites. It just takes time. About the only kind I know, which is almost impervious to rot is black locust or Osage orange.

I doubt that rusting steel or iron will contaminate your soil. Where I grew up much of the soil was bright orange from all of the iron in it. The larger town, just down the road was called Red Bank.

George
Tahlequah, OK

Personally, I wouldn't be too quick to raise my beds. In our climate, level or even slightly sunken seems to work best for me.

Newbie,

The program that certifies organic farms allows the use of composite lumber like Trex in growing operations that are certified organic, so it seems likely that there is nothing in it that would leach anything toxic into the soil.

Like George, I don't know of much wood that won't rot. I've never used redwood because it is cost prohibitive, and even cedar rots. Osage orange or black locust fence posts here in my part of the state can last up to 50 years, although once you remove them you may find quite a lot of the post did rot while underground---just not enough for the fence post to fall over or collapse.

Like George, I doubt rusting steel or iron would leach into the soil enough to damage the soil or plants grown in it. The Noble Foundation wouldn't advocate the use of corrugated metal beds if they felt there was any risk involved in using them. They're all about science and research and doing things properly.

The Medina Orange Oil you linked is exactly the same one I buy and use. It is very strong and must be diluted a great deal. It makes a great soil drench for fire ant mounds, among other things. If not diluted enough, it makes a great paint stripper--so be careful how you us

There are many soil dwelling critters that will eat wood, including carpenter ants. If you haven't seen any termites, I wouldn't worry about them. If they should pop up at some point in time, there are ways to deal with them. As George pointed out the wood likely just rotted due to constant contact with the soil.

I've grown in raised beds lined with wood since the early 1980s and never have seen a termite in or near any of them. I'm not saying it never would happen, just that it isn't very common here.

You could hammer a few inexpensive grade stakes into the ground now near the area where you intend to build your raised beds and see what happens to them over the course of the next few months. Think or them as termite traps.

As much as I like raised bed, I agree with George that in some situations, grade-level beds may be better----because they don't warm up as quickly and because they don't dry out as quickly as soil in raised beds will dry out. Much depends on a complex combination of factors including how well your soil drains (or doesn't drain), how windy and exposed your garden plot is, how much rain you do or don't get during the growing season, etc.

All of my garden is not raised beds. I have raised beds in the sloping uphill portions of my main veggie garden, which has mostly well-amended red clay soil, and couldn't garden without them. That soil in that area, even when well-amended, tends to drain very slowly. In the wettest part of the wettest years, even plants in the raised beds can stay too wet and can rot. I don't have raised beds at the western end of the garden where there is a very fast-draining sandy/silty blend. The soil there drains too quickly, a problem that would be even worse with raised beds above grade level. For the first 5-6 years here, even with constant watering, it was hard to keep anything alive in that sandy soil because it just wouldn't hold water long enough. Eventually I amended it enough that it now holds moisture well, but still not well enough that I'd put raised beds there. So, you have to consider your soil and how well is drains when you decide what kind of beds to use In my new garden plot out west of the barn, the soil drains incredibly fast in much of that garden, while there's a few really clayey slow-draining clay. In the fast-draining sandy soil back there, I almost could have waffle beds (sunken below grade level) except for the fact that every now and then we have a big, slow-moving storm system dump 6-9-12+" of rain in one day, and I think that waffle beds on a day like that might turn into ponds with dead plants in them. This is only its second year and I haven't amended the soil much yet and I doubt I'll ever be able to get it to hold moisture well enough in typical weather that I'd want to build raised beds back there. In fact, I'm fairly sure I'd never put a raised bed out there unless it was a hugelkultur bed, and my fear or snakes has kept me away from hugelkultur beds here so far.

Dawn

Newbie'
I have owned and built for others raised beds using concrete blocks that measure 8x16x4. Sometimes these blocks can be obtained as 2nds from Dolese plant in SW OKC: Cheaper! They will never wear out.
If ground is level, then each block need not be staked or secured with metal rods, perhaps only at corners. Grass invasion will occur some, but is minimal and easily removed.
daleok