Create an inexpensive and easy centerpiece using food coloring and simple white flowers in bud vases. I like the idea of the colored water with maybe white roses and the colors of the water would be the colors of the wedding
Make a backyard bowling alley. Add food coloring to clear plastic bottles of water. Use party streamers as lane margins. Add glow sticks for night bowling. (These would make great outdoor table nightlights also with the glowsticks, gonna try it!