I have seen so many ideas for "home remedies" for flower food. The floral industry is a science, and the professional products are so affordable that I cannot fathom why someone would risk pay so much for their wholesale wedding flowers, yet want to scrimp or forget about the flower food and other fresh flower products.
These flowers travel all the way from the farms (usually in South America) to your doorstep. They are dry and thirsty and it's critical that you hydrate them properly immediately upon arrival and feed them the right combination of food and clean water to extend the life of every flower.
If you need convincing of how important this is, please take a few minutes to watch these tutorials: