I'm having an outdoor wedding and I found a picture of a beautiful centerpiece that I'm in love with. It's very tall curly willow with greenery and white flowers added as well. I need it to be tall enough for the guest to be able to see under the main part of the flower to see the guest on the other side of the table. The "stem" is very narrow, so I'm trying to find tall, narrow vases (20"x5")(Any suggestions as to where to buy theses cheap?????). My only fear is they will blow over if it's a windy day. Do you have any ideas of how to keel these centerpieces stable?