In addition to painting, you can also try parging:
http://www.backwoodshome.com/articles/leonard57.html

Or ask your hardware store and see what they have for exteriour stucco
and tiles. Home Depot had a faux brick stencil for concrete walls a
few years ago. There was a pattern for stone as well. The cheapest
planter is just a raised bed.


Ornata wrote in message ...
Popcorn Lover Wrote:
I'm interested in building some inexpensive planters for our driveway.
I want them to be about 12' long, 2' wide and 2' tall, with open
bottoms for drainage.

I thought of making them with 8x8x16 concrete blocks which are a whole
lot less expensive but they'd be pretty ugly that way, wouldn't they?

--
- Popcorn Lover
QUOTE]
Concrete can be painted to make it more attractive. It's worth
remembering that it's a very alkaline material and consequently would
raise the pH of the soil in the planter (this would be a problem if you
were hoping to grow lime-hating plants). Could you maybe use treated
timber, lining the inside of the planter with thick polythene to
prevent the wood coming into contact with the compost? I know they
wouldn't last forever.