Cut flowers bring the colors of the garden inside. Whether you cut flowers from your own garden or want to prolong the life of a purchased bouquet, cut flower food provides the nutrients the blooms need to survive. Once removed from their root system, flowers no longer have access to the nutrients in the soil. Adding a flower food or preservative to the water in the vase provides them the nutrition they would otherwise lack. Make your own cut flower food if you don't have any commercial preservative on hand.
Mix 2 tsp. sugar, ½ tsp. chlorine bleach, ¼ tsp. alum with 1 quart of warm--100 to 110 degrees F--water. Alternately, use 2 tbsp. white vinegar instead of the alum. Add the mixture to the vase or flower container.
Strip away any leaves that will sit beneath the water. Hold the end of the stem under running water and cut the end off at a 45-degree angle with a sharp, clean knife.
Place the cut stems immediately into the vase with the plant food mixture. Place the vase in an area out of direct sunlight.
Replace the plant food mixture in the vase if it becomes cloudy or discolored, or once every five days. Re-cut the ends of the stems if the stems become weak.