When picking a background for the formal photos at a wedding, it's really important to remember one thing. The bride gets to pick. But if in her wisdom she allows you to have any sort of say in the decision, try and pick backgrounds that sort of complement the theme of the wedding. For example, this couple had a very sort of beachy, coastal style wedding, and we've picked a beautiful sunset, beautiful rock formation, and the waves crashing in the background.
Another couple we photographed had got married at a vineyard, so the greens and the lakes were just a beautiful background for what they wanted in their wedding photography. Remember to try and pick your background with color in mind. If we've go back to that first couple, for example, you'll notice that there's no external color apart from the white of the wedding dress and the black of the groom's suit. Any other color there would have possibly clashed with the sand or the blue sky. In our third image, you'll notice that it's completely classic.
Beautiful bouquet, so for me it was important to have a lot of garden, a lot of color, and a lot of vibrancy in that photograph as well. Also, because the bouquet was white, I really wanted to bring some external color in as well, and the green really worked to help that happen. When picking the background of the wedding, remember the bride is always right, but hopefully she lets you make some of the decisions as well.