The tulip is a perennial, bulbous plant with showy flowers in the genus Tulipa, of which around 75 wild species are currently accepted and which belongs to the family Liliaceae.
Tulips are indigenous to mountainous areas with temperate climates and need a period of cool dormancy, known as vernalization. They thrive in climates with long, cool springs and dry summers. Tulip bulbs imported to warm-winter areas of are often planted in autumn to be treated as annuals. Tulip bulbs are typically planted around late summer and fall, in well-drained soils, normally from 4 to 8 inches (10 to 20 cm) deep, depending on the type. Species tulips are normally planted deeper.
Tulips can be propagated through bulb offsets, seeds or micropropagation. Offsets and tissue culture methods are means of asexual propagation for producing genetic clones of the parent plant, which maintains cultivar genetic integrity. Seeds are most often used to propagate species and subspecies or to create new hybrids. Many tulip species can cross-pollinate with each other, and when wild tulip populations overlap geographically with other tulip species or subspecies, they often hybridize and create mixed populations.
The tulip was a topic for Persian poets from the thirteenth century. In his poem Gulistan Musharrifu’d-din Saadi,described a visionary garden paradise with ‘The murmur of a cool stream / bird song, ripe fruit in plenty / bright multicoloured tulips and fragrant roses…’ The gift of a red or yellow tulip was a declaration of love, the flower’s black center representing a heart burned by passion. In recent times, tulips have featured in the poems of Simin Behbahani.
During the Ottoman Empire, the tulip was seen as a symbol of abundance and indulgence. The era during which the Ottoman Empire was wealthiest is often called the Tulip era or Lale Devri in Turkish.
In 2009, two other subgenera were proposed, Clusianae and Orithyia, and this total of four subgenera was corroborated by a recent study (Christenhusz et al. 2013). That study did not find support for any of the previous sections proposed, and since hybridisation is relatively common, it is probably better to refrain from subdividing the subgenera any further. Some species formerly classified as Tulipa are now considered as the separate genus Amana, including Amana edulis (Tulipa edulis). These species are more closely allied to Erythronium.