For a column you can use the same guidelines as for a spiral arch. With balloon clusters of four, you will need 12 x 5 inch balloons per foot. That makes 72 balloons. Add a few in to cover for balloons bursting.
Good luck with your balloon column.
And as always, we would love to see a photo of your balloon decoration (it does not have to be from a wedding, pictures from birthday parties or other events are welcome too).
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