Bridal bouquet flowers that show either a distinct curve trailing down to the right or left (or both sides!) is referred to by florists as "crescent" shaped. This is a different spin on the tradition cascading bouquet that trails down the front of the gown.
As discussed on the cascading bouquet page, I recommend that you use a Floralock Stem Adhesive to be sure all the long stems inserted into slanted Belle Bouquet Holders do not drop out on the way down the wedding aisle.
I usually recommend that you order the largest bouquet holder, as the water pulled daily by living flowers will surprise you. I do show step by step how to process your wholesale flowers correctly upon delivery.
Many flowers, such as tulips, calla lilies, and snapdragons already have a natural curve to the flowers that you can use to shape your crescent bouquet. Softer stemmed flowers can be rolled gently in your fingers to encourage that natural curve.
Be careful, however, with the firm straight flower stems that you don't get over ambitious and snap the stems off while trying to create the curve. If this should happen, don't throw the blooms away, simply give them a clean cut with your floral knife and insert the cut end into a shallow cup of water for use in corsages and boutonnieres.