i am doing a project on a lily and i need to know if it reproduces asexually, sexually or both

a lilium -lily
trumpet lily

The Tiger Lily can be reproduced both asexually and sexally (requires another plant, the lily itself is self-sterile)
Sexual propagation:
http://www.mikesbackyardgarden.org/lilyprop2.html
Asexual propagation (several methods)
http://www.mikesbackyardgarden.org/lilyprop.html