An eco-friendly wedding menu and decor focuses on less waste, and more reusables, such as glass, and cloth for the tablescapes; if possible, refrain from fresh flowers which are usually discarded, and opt for potted plants, and even tastefully executed silk floral arrangements, or natural centerpieces featuring greenery, seashells, as examples.
For the food, push vegetable-centric dishes more to the forefront, and serve a lot less meat. If you decide to feature seafood, make sure it is not on the endangered list. Go for organic wines and beers, and if possible, have an organic ingredient wedding cake.
Caffeine-free teas and fair-trade coofees are also a plus.