I was looking up trellis' on Lowes website and stumbled across a new product they're going to be getting in February.. They're composite boards made of wood fiber and recycled plastic! Now, the posts are a little over $30 so if you're going for a fence it might get pretty pricey.. But the rail boards themselves are 1 1/2" x 3 3/4" x 71 3/4" and cost about $12.. Yes, they cost a little more than regular wood would cost, but just imagine how long they'll last.. And they're made from recycled plastic.. I absolutely love products made from recycled plastics.. Anyway, come February I'll be making a weekly trip to Lowes to buy a board or two at a time.. Unfortunately that's all our budget might allow for now, buying the supplies a bit at a time..
If you want to look them up on the Lowes website, they're in the fencing section under wood fencing..
Since they're only about 6 foot long, I might have to do 4'x4' beds.. That's ok though because I can use the extra 2 foot leftovers on the inside of the bed to attach the top and bottom sections..