[header] How to prevent hyacinth flowers from flopping [title] Choose a location with good light to plant your bulbs. [step] Hyacinths need about 5 hours of light each day in order for the stems to grow strong. In weak light, the stems will be thin and the blooms will easily snap the stalk. 
[title] Plant hyacinth bulbs 4 inches (10 cm) deep. [step] If the bulbs aren't planted deep enough, the plant's stem won't have enough strength to support the weight of the flowers when the hyacinth blooms.