Anyway I wanted to at least write one entry in May and the olde symbol of this month of growth, is the maypole. Of course I failed to get it done in time, but I'll post it anyway (even though we are in June now, hush hush ;-) )
The maypole is an ancient way of celebrating the spring, often associated with festivals of fertility. Young unmarried boys and girls would dance in a circle around the pole.
Midsummer is another time where poles where included in celebrations, probably it represents fertility with it's phallic shape which goes well with a wedding that is sometimes followed by a baby or two ;-). It has also been argued that it can represent the tree of life, Ygdrasil from the Norse mythology. Dancing around the tree of life doesn't make it any less fit for a wedding I think.
It probably derives from ancient times, when the germans and scandinavians weren't yet christians. I really like this idea because it's festive, fun and slightly heathen.
The poles with bright ribbons can be used both for a reception activity and decorations like in the first picture. The strings can either be attached to a wheel that can turn so the dance can go on and on, or just be bound to the top, so the dancing will result in the pole quickly being wraped in a colorful braid.
This picture I found on Flikr, from a medieval wedding, where the guests participated in the dance around the pole, intwining the colorful bands.
Have fun dancin at you wedding whether around a pole or not :)