Tall Centerpieces

So we've established that we need tall centerpieces in our reception venue because of the height of the tent, but i'm having a hard time figuring out what those centerpieces should look like. I KNOW that i want it look very garden-like - loose arrangements, garden florals, very soft and romantic - but i'm having a hard time translating that look into a tall centerpiece. Most arrangements that i see that i like are low centerpieces that are in small urns or something.

I have found a few centerpieces that i like the shape and composition of...but you just have to ignore the colors in some of these pictures here...






What do you guys think? Any suggestions?