Tulips began to be cultivated in the 10th century in Persia although they have been found in Europe, Asia and North America. There are about 76 species of tulips that are grown from bulbs that bloom every spring. They grow naturally in mountainous regions and they are planted as annuals in warm winter climates. They come in a variety of colors except for pure blue; depending on the variety, tulips can be anywhere from 4 to 28 inches high. Tulip flowers grow from a single stalk, the stems have few leaves and the flowers resemble a cup or are star shaped. Today, tulip festivals are held in all parts of the world including North America, the Netherlands and Australia to celebrate these beautiful flowers.