One of the most striking palms is the Triangle Palm. The Triangle Palm is definitely an eye catcher. The Triangle Palm can be the centerpiece of your landscape. The appeal of its large feather-like leaves that can grow up to 13 feet long with the maximum average height of a Triangle Palm can reach over 20 feet and its trunk can reach over 2 feet in diameter. The Triangle Palm leaves usually spread over 10-20 feet long from tip to tip.