I wouldn't have thought to use a zip tie to join balloons, but it sure does work! I did this with green balloons for Emery's Dora party to make trees for the forest, as part of the scavenger hunt. We hung lots of brown streamers from them to make trunks.
To make a confetti-filled balloon bouquet, first, grab a clear and white balloons. Then, grab a mini handful of tissue paper confetti. Fold the pile of confetti in half, and then in half again. Once you have a little tube of confetti, push the confetti-tube into the neck of the balloon. Poke down until the clump of confetti falls into the balloon. Fill with helium . Add a ribbon tie and you’re DONE!