How can I keep flowers fresh for days

I love flowers, but I find they do not last long. I know some florists use plant food, but where I live they do not provide plant food at all. So, I am constantly ensuring the flowers are well hydrated. You can keep them hydrated by changing the water and filling the vase with enough water to ensure they can absorb well.  I hope my tip helps. 

In the interest of science, we bought a bouquet so we could test five additives people commonly put in water to try to make fresh flowers last longer:

• Vinegar and sugar mixture. The common wisdom is that vinegar will mitigate bacteria, and sugar will act as food.
• Conventional flower food.
• Bleach. The idea is that a teaspoonful will kill bacteria.
• Aspirin: To increase the acidity of the water
• A penny: The copper allegedly acts as an antibacterial agent.

Here's what we learned: 

By: Erin Boyle