Maryland Code, Land Use § 10-303

(b)(1) The Mayor and City Council of Baltimore City shall hold at least one public hearing on a proposed zoning regulation or boundary at which parties in interest and citizens have an opportunity to be heard.

(2) The zoning regulation or boundary may not become effective until after the hearing or hearings.

(1) post a similar notice at a place designated by the respective zoning authorities within the district or zone proposed to be changed; and

(2) mail notice of the proposed change by United States first-class mail to any person whose name last appeared in the Baltimore City tax records as the owner of the property proposed to be changed.