La. Stat. tit. 33 § 4780.4
The governing authority of St. Helena Parish shall, in accordance with the comprehensive plan required by R.S. 33:4780.3, provide for the manner in which the regulations and restrictions and the boundaries of the districts shall be determined, established, enforced, and, from time to time, amended. No regulations or restrictions shall become effective until after a public hearing held by said governing authority at which parties in interest have had an opportunity to be heard. Notice of the time and place of the hearing shall be published once a week in three different weeks in the official journal of the parish, and at least fifteen days shall elapse between the first publication and the date of the hearing. In addition to notice by publication, and at least ten days prior to the hearing, a good faith attempt to notify the owner or owners of record of the properties to be zoned or rezoned shall be made by the sending of an official notice by regular mail of the time and place of the hearing and subject matter of the regulations and restrictions. Notwithstanding the foregoing, when more than ten parcels are to be zoned or rezoned by enactment of a zoning ordinance, the advertisement in the official journal required herein shall be considered adequate notice to the property owners.
La. R.S. § 33:4780.4