How can I make a rectangular planter for my house?

I'm trying to make a low,long rectangular planter to put dried bamboo or dried branches in, to divide my living room from my kitchen. I don't want to use floor vases because they would be too bulky. I'm assuming I'm going to have to use cement so that the stick can actually stand...I'm just new to the whole DIY thing, and especially to using cement so I could use some tips.