Well you definitely need drainage. Drilling holes would work, though I'm not sure of how many. Otherwise you'll have an anaerobic, rotted mess at the bottom.

I feel like a potting mix might be the best way to go here. It's basically just a big container. If it were sitting on the ground, with no bottom, then I would say use soil. As for what kind of mix, well I'll let others recommend that. You might want to make your own concoction, though. Certain vegetables like certain fertilizers, so you can control what goes into the mix by doing it yourself. A 1:1 ratio of sphagnum peat moss and perlite might be a good start. What's the depth of that bed?

You might want to post this in the Container Gardening forum, believe it or not.

Thanks Chris! The depth of the bed is 12 in.

I too recommend the Container forum. If you don't want to make your own and save a few bucks, you can buy potting or container mix at the store. Just avoid things labeled 'garden soil', soil amendments, topsoil, compost, etc.

Is that plain untreated pine? It's going to rot. :-]

Yes its pine untreated.. I went that way because of the possibility of treated lumber leeching into garden. I still think taht I could get about 5-7 yrs out of the pine. Im planning to wrap and cover it for the winter...

Cedar would last longer, and is naturally resistant, but not forever. It will be more work, but it may still be cheaper to make another one out of pine when that one rots lol. Cedar is very appealing, but just so darn pricey. I just made a 3'x6'x1' bed using knotty cedar and it was about $120 for the lumber. I did go to a lumberyard though, and they are always more expensive :-/

Also, treated lumber, nowadays, no longer uses CCA(chromated copper arsenate). I believe there was a law that banned that in late-2003. However, I understand how it would give you peace of mind, knowing you didn't use it.

What did you use for the bottom of that bed? Doesn't look like plywood.

Hi Chris.. Yeah I saw the cost of cedar. I went with the pine... But I paid about 70-80 for lumber and supplies. The bottom of the bed is actually plywood from Home Depot 4X4.

What you have is less a raised bed than a large container, of a type often built for handicapped people. Some places that have these planters use potting soil as you would with any other container or they have used a good soil which would be something like 45 percent sand, 25 percent silt, 25 percent clay, and 5 percent organic matter. If you use a good quality soil as described the only amendment that may be needed would be some compost to bring the amount of organic matter up to about 6 to 8 percent.

Drainage is very important and the holes you will need to drill in the bottom can be covered with a find mesh window screen that will help hold the soil in place.

kimmq is kimmsr

You might consider plastic decking lumber, especially for the bottom which no one sees. It's made of sawdust and recycled plastic bags, i.e. polyethylene, which doesn't have other stuff (plasticizers) in it.

The 'new' treated lumber has "copper quat" which is basically copper soap similar to what you can get in a bottle for fungus control. Although it is not particularly toxic, I suppose a buildup of copper may not be a great thing for plants. However I haven't researched that angle in detail.

That's a great point. Never thought of something like Trex. Pricier than lumber, but it will be a one-time purchase.

You can also line the inside with weed block. Typically that was used when you have slats in the bottom, to hold the soil in. However, I think you could still use it as you will be making holes in the plywood bottom.

It's a good looking elevated raised bed.