Most women want fresh flora for their wedding party's bouquets and boutonnieres. They are great if you have a place of to keep them and can afford how pricey they can be. In the spring and summer they are not that bad, however during the months where nothing grows, fresh flowers can be very pricey depending on what kind it is that you want. In these months it is usually better to use artificial ones. They won't die on you, not matter where you store them and they are going to fit your wedding budget.
Artificial flowers are also great when you are wanting to coordinate interesting colors together. Most fresh flora can be dyed, however artificial ones already come in the colors you want so that you are saved the money and hassle from dying them. Dye also makes fresh flowers die quicker, so you risk having dead flora for your wedding day.
When you chose the colors for your bouquets, you want to make sure that everything coordinates as much as possible. You can have artificial and fresh flowers matched to the colors of your bridesmaid dresses. Most brides use white roses in the bouquets. It is traditional and very elegant, however if you are not crazy about the idea of using even more white, then that's fine. All colors look great with a white dress.
Usually if you go with your guy feeling then you won't go wrong on your bouquets. The main thing to remember is that if you want to keep your own bouquet for sentimental reasons, make sure that you have a spare one to throw at the reception. Even if you use fresh flowers throughout your entire wedding, it's fine to have the spare bouquet made of artificial flowers, that way the person catching it will be able to have it as a keepsake forever.