La. Stat. tit. 33 § 140.54
The police jury of the parish shall provide for the manner in which the regulations and restrictions and the boundaries of the districts shall be determined, established, and enforced, and from time to time, amended. No regulation or restriction shall become effective until after a public hearing at which parties in interest have an opportunity to be heard. A public hearing in regard to the regulations may be held by the governing authority of the parish. In such case notice of the time and place of the hearing shall be published at least once a week during three different weeks in the official journal of the parish, or if there be none, in a paper of general circulation therein. At least fifteen days shall elapse between the publication and the date of the hearing.
La. R.S. § 33:140.54