The more you can learn about fresh cut flowers and their special care, the healthier your arrangements will be.
Lets start with vases & containers. Most people will grab a vase out of the cupboard and fill it with water and place the flowers in it. I would like to suggest that you rinse it first with hot water and get any dust out of it. Then put a few drops (and I do mean only drops) of bleach. This will keep out and kill any bacteria and it will not harm the flowers. When you buy flowers, most places will supply a packet of flower food. If you have no flower food, not to worry, you can always put a teaspoon of sugar in the water.
Now you are ready to prepare your flowers.
Take each stem and remove any leaves that may be below the water line. You do this so you don’t get microbial damage to your flowers. Leave as many leaves as possible above the water line as this is a design element. When you are dealing with roses, most people like to remove the thorns but I recommend that you leave as many thorns on as possible. This is because stripping them off causes wounds to the rose and allows possible microbial invasion causing your roses to die sooner than they need to.
You will want to cut about an inch off the bottom stems. Cut them at an angle with a sharp knife preferably under water. You do this so that the flowers drink water, not air. You can get air pockets in the stem preventing them from drinking which ensures early death.
There are some flowers that require special handling. Such is the case with freesia. This flower does not take well to chlorine so you’ll want to use distilled water. Tulips do better in a vase with a penny on the bottom. The petals stay closed a little longer. Note, tulips can still grow after they have been cut, as much as an inch per day! Wilting hydrangeas prefers being in a vase. This is because it needs to be hydrated. If you put them in floral foam, their life span will be much shorter. Note, if your hydrangea shows signs of wilting, you can revive them by turning them upside down in water for about an hour.
Some flowers last longer than others, such as carnations and daisies. They can last as long as 3 weeks. An arrangement with roses and lilies will not last as long, usually 4 to 7 days. Determine what you want the flowers for.