Petals are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the corolla. Petals are usually accompanied by another set of modified leaves called sepals, that collectively form the calyx and lie just beneath the corolla. The calyx and the corolla together make up the perianth, the non-reproductive portion of a flower. When the petals and sepals of a flower are difficult to distinguish, they are collectively called tepals. Examples of plants in which the term tepal is appropriate include genera such as Aloe and Tulipa. Conversely, genera such as Rosa and Phaseolus have well-distinguished sepals and petals. When the undifferentiated tepals resemble petals, they are referred to as "petaloid", as in petaloid monocots, orders of monocots with brightly colored tepals. Since they include Liliales, an alternative name is lilioid monocots.

फूल के हरी पंखुड़ियों के भीतर दलचक्र स्थित रहता है। ये प्रायः रंगीन होते हैं तथा इनमें सुगन्ध भी मौजूद रहती है। रात के समय खिलने वाले पुष्पों के रंग सफेद होते हैं तथा उनमें तेज सुगन्ध होती है। दल चक्र के एक भाग को दल कहते हैं।