At one brother's wedding we purchased hanging baskets at a local garden store, took off the hangers (save the hangers), set them in the middle of the table and put votive candles around them. It turned out beautifully and at the end of the reception each important person in the bride and groom's life took home a beautiful hanging basket too.

Call your local store, garden, home depot, walmart, etc, tell them what you plan and ask them to set aside the prettiest baskets when they are delivered to their store. Usually they are happy to do it, and some will throw in a discount too