The term “hyacinth” is used to refer to several flowering plants, including the common hyacinth, grape hyacinth, and water hyacinth. All three are widely cultivated around the world in gardens, and many have a history of cultivation which extends back through many centuries. Garden supply stores often carry hyacinths for people who wish to plant them, and special cultivars can also be ordered directly from companies which breed hyacinths.
Common hyacinths are bulbs in the genus Hyacinthus. These bulbs produce broad leaves and racemes of tightly clustered bell-like flowers. Common cultivars come in blue, pink, and white, and cultivation of the common hyacinth is especially common in Holland, a historical powerhouse of bulb breeding. Most cultivars are representatives of Hyacinthus orientalis, a species which emerged in the Middle East.
According to legend, hyacinths sprang up around the body of the Greek hero Hyacinth which he was accidentally slain by Apollo. Other stories say that the bulbs came from a mixture of Apollo's tears and Hyacinth's blood, since the gods could not bear to allow Hyacinth to travel to the underworld after his death. The precise flower which emerged after Hyacinth's death is a topic of debate; it may have been an iris or another bulb, rather than the common hyacinth, as descriptions of the event are a bit sketchy.
Grape hyacinths are bulbs in the genus Muscari which produce distinctive clusters of flowers which look sort of like grapes. Grape hyacinths commonly come in a purple color, enhancing the resemblance, and they have delicate, spiky leaves. Grape hyacinths are among the earliest of spring bloomers, and they thrive in a wide variety of soil and weather conditions. Their bulbs are also edible, incidentally.
Water hyacinths, on the other hand, are plants which have evolved to live on the surface of lakes and slow moving streams. They have fleshy leaves with bulb-like appendages to help them float, and they spread with the use of runners. Water hyacinths are notorious for spreading rapidly, choking out other species and creating stagnant water, but they are also quite attractive, producing stalks of delicately colored flowers which lead some people to cultivate water hyacinths as ornamentals.