Whichever way you decide to go with your flowers, a lovely idea is to try and tie your whole theme together so if you're going for roses, then have a rose design featured somewhere within your headdress. Look out for a company who can work with you and your designs and most importantly your budget to create that one_off, bespoke creation just for you.
While selecting the flowers for your wedding you should take care to blend it with the theme of your wedding. Even the flower selection would depend on your theme as well as the season that you are getting married in. If you want flowers that are not available in the season, you would have to tell your flower decorator in advance to make arrangements to procure the flowers for your wedding. Even though it would turn out to be more expensive but if you can afford it and that is what would make your dream wedding come true, you should go ahead and book your self a good and experienced florist who can easily turn your dreams into reality.