Amaryllis is a flower available throughout the winter months. This flower is found in shades of red and white. Because this flower is in season during the winter months, this is a good choice for a wedding on a budget.
Holly is inexpensive this time of year. Freesia is in season during winter months also. Both make for terrific fragrance enhancers.
Of course there is always the poinsettia, use those to decorate the church, or to use as centerpieces. These are quite plentiful in colder months and can be found in several different colors.
You may also want to consider purchasing silk flowers. Silk flowers can cut costs down a bit if you really want a certain flower that may not be in season. As out of season flowers tend to come with quite a large price tag.
If you plan your wedding well in advance visit craft and hobby stores after the holiday season to stock up on different items pretty inexpensively. Consider filling large glass vases with pine cones and different size and shapes of glass ornaments. Drape twinkle or icicle lights around your head table or up above the dance floor for a stunning look. Use different holiday decoration themes for your wedding; try snowmen, gingerbread men, candy wonderland, or snowflakes.