Keep water full.
Fresh blooming flowers drink a lot of water. You need to add water daily for the flower life last longer.

Flower arrangement in a vase of water
Change water every two to three days. Cut the stems about one inch in a bowl of fresh water helps flower life last longer.

Flower arrangement in green floral form (oasis).
Floral form is absorbing water, and hard to change the water. We added preservatives and nutrition when we created the arrangements. Add water until the container is full, this helps flower last longer.

Keep away from direct sunlight, wind or heat.
Most of flowers like cool spot (65 to 72 degrees Fahrenheit). Away from direct sunlight, heating or cooling vents, under ceiling fans, or on top of televisions, heaters, raditor or any appliances which discharges heat.