Your hyacinths may arrive with closed buds, but will open over the next few days after conditioning. Start with a very clean vase. Hold each hyacinth next to your vase to gauge how much stem you'll need to trim; you might also want to remove some of the leaves. Using a sharp knife or pruners, cut stems at a 45-degree angle so they don't sit flat on the bottom of the vase, for better water absorption. Be sure to cut away the firm, white portion, or flowers will have difficulty drawing water.
Hyacinths last longer in shallow water. They have a tendency to make water cloudy, so be sure to change it daily. Add the included cut-flower food to the vase; use the extra pack with your first change of water. Hyacinths should be reconditioned every two to three days: Recut the stems, change the water, and add food. To nourish flowers after the flower food is used up, refill your vase with a solution of one teaspoon of sugar and two drops liquid bleach per gallon of fresh, cold water. Keep flowers in a cool area.